claws-mail: add curl dependency
claws-mail: add curl dependency

* it's needed by libetpan:
  | configure:20812: checking whether libetpan-config hints compiles and links fine
  | configure:20826: arm-oe-linux-gnueabi-gcc  -march=armv5te -marm -mthumb-interwork --sysroot=sysroots/qemuarm -o conftest -O2 -pipe -g -feliminate-unused-debug-types -Wno-unused-function -Wno-pointer-sign -Wall   -Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed conftest.c  -lm  -Lsysroots/qemuarm/usr/lib -letpan -pthread -Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed -lcurl -lgcrypt -lgnutls -lz -lexpat -lgnutls -llockfile >&5
  | sysroots/x86_64-linux/usr/libexec/armv5te-oe-linux-gnueabi/gcc/arm-oe-linux-gnueabi/4.8.1/ld: error: cannot find -lcurl
  | collect2: error: ld returned 1 exit status

Signed-off-by: Martin Jansa <516df3ff67e1fa5d153800b15fb204c0a1a389dc@gmail.com>

victronenergy/meta-openembedded,VCTLabs/meta-openembedded,epylar/meta-openembedded,trikset/meta-openembedded,kraj/meta-openembedded,rehsack/meta-openembedded,joelagnel/meta-openembedded,martiert/meta-openembedded,victronenergy/meta-openembedded,tobw/meta-openembedded,tobw/meta-openembedded,schnitzeltony/meta-openembedded,trikset/meta-openembedded,openembedded/meta-openembedded,trikset/meta-openembedded,VCTLabs/meta-openembedded,RealDigitalMedia/meta-openembedded,rehsack/meta-openembedded,amery/meta-openembedded,schnitzeltony/meta-openembedded,rofehr/meta-openembedded,rdm-dev/meta-openembedded,fredcadete/meta-openembedded,epylar/meta-openembedded,rdm-dev/meta-openembedded,victronenergy/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,shr-distribution/meta-oe,dongkc/meta-openembedded,openembedded/meta-openembedded,lixinfnst/meta-openembedded,rdm-dev/meta-openembedded,tobw/meta-openembedded,rofehr/meta-openembedded,joelagnel/meta-openembedded,mrchapp/meta-openembedded,akuster/meta-openembedded,kraj/meta-openembedded,RealDigitalMedia/meta-openembedded,VCTLabs/meta-openembedded,schnitzeltony/meta-openembedded,epylar/meta-openembedded,shr-distribution/meta-oe,lixinfnst/meta-openembedded,akuster/meta-openembedded,amery/meta-openembedded,rofehr/meta-openembedded,amery/meta-openembedded,lgirdk/meta-openembedded,openembedded/meta-openembedded,kraj/meta-openembedded,MCherifiOSS/meta-openembedded,martiert/meta-openembedded,kraj/meta-openembedded,RealDigitalMedia/meta-openembedded,mrchapp/meta-openembedded,VCTLabs/meta-openembedded,rdm-dev/meta-openembedded,rdm-dev/meta-openembedded,mrchapp/meta-openembedded,RealDigitalMedia/meta-openembedded,RealVNC/yocto_imx6sabreauto_meta-openembedded,lgirdk/meta-openembedded,fredcadete/meta-openembedded,dongkc/meta-openembedded,lixinfnst/meta-openembedded,lgirdk/meta-openembedded,dm8tbr/kodi-wip,amery/meta-openembedded,dm8tbr/kodi-wip,dm8tbr/kodi-wip,joelagnel/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,mrchapp/meta-openembedded,epylar/meta-openembedded,lixinfnst/meta-openembedded,RedFIR/meta-openembedded,VCTLabs/meta-openembedded,MCherifiOSS/meta-openembedded,akuster/meta-openembedded,rehsack/meta-openembedded,fredcadete/meta-openembedded,martiert/meta-openembedded,moto-timo/meta-openembedded,dm8tbr/kodi-wip,trikset/meta-openembedded,victronenergy/meta-openembedded,martiert/meta-openembedded,shr-distribution/meta-oe,VCTLabs/meta-openembedded,VCTLabs/meta-openembedded,epylar/meta-openembedded,fredcadete/meta-openembedded,dm8tbr/kodi-wip,moto-timo/meta-openembedded,lgirdk/meta-openembedded,akuster/meta-openembedded,tobw/meta-openembedded,kraj/meta-openembedded,trikset/meta-openembedded,MCherifiOSS/meta-openembedded,RealVNC/yocto_imx6sabreauto_meta-openembedded,rehsack/meta-openembedded,akuster/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,openembedded/meta-openembedded,RedFIR/meta-openembedded,dongkc/meta-openembedded,openembedded/meta-openembedded,rdm-dev/meta-openembedded,RedFIR/meta-openembedded,openembedded/meta-openembedded,lgirdk/meta-openembedded,lgirdk/meta-openembedded,RedFIR/meta-openembedded,lixinfnst/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,RedFIR/meta-openembedded,openembedded/meta-openembedded,mrchapp/meta-openembedded,rofehr/meta-openembedded,moto-timo/meta-openembedded,mrchapp/meta-openembedded,schnitzeltony/meta-openembedded,joelagnel/meta-openembedded,RedFIR/meta-openembedded,RealDigitalMedia/meta-openembedded,epylar/meta-openembedded,mrchapp/meta-openembedded,rehsack/meta-openembedded,lgirdk/meta-openembedded,shr-distribution/meta-oe,MCherifiOSS/meta-openembedded,lixinfnst/meta-openembedded,joelagnel/meta-openembedded,trikset/meta-openembedded,martiert/meta-openembedded,schnitzeltony/meta-openembedded,dm8tbr/kodi-wip,dongkc/meta-openembedded,tobw/meta-openembedded,rdm-dev/meta-openembedded,joelagnel/meta-openembedded,fredcadete/meta-openembedded,MCherifiOSS/meta-openembedded,dm8tbr/kodi-wip,RealVNC/yocto_imx6sabreauto_meta-openembedded,victronenergy/meta-openembedded,trikset/meta-openembedded,epylar/meta-openembedded,schnitzeltony/meta-openembedded,RealVNC/yocto_imx6sabreauto_meta-openembedded,joelagnel/meta-openembedded,openembedded/meta-openembedded,fredcadete/meta-openembedded,epylar/meta-openembedded,rofehr/meta-openembedded,amery/meta-openembedded,rehsack/meta-openembedded,RedFIR/meta-openembedded,RealVNC/yocto_imx6sabreauto_meta-openembedded,dm8tbr/kodi-wip,rehsack/meta-openembedded,joelagnel/meta-openembedded,kraj/meta-openembedded,trikset/meta-openembedded,schnitzeltony/meta-openembedded,dongkc/meta-openembedded,shr-distribution/meta-oe,sigma-embedded/elito-org.openembedded.meta,MCherifiOSS/meta-openembedded,amery/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,shr-distribution/meta-oe,fredcadete/meta-openembedded,sigma-embedded/elito-org.openembedded.meta,RedFIR/meta-openembedded,rofehr/meta-openembedded,VCTLabs/meta-openembedded,tobw/meta-openembedded,moto-timo/meta-openembedded,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