ios: Pass the right architecture as --host when building contribs
ios: Pass the right architecture as --host when building contribs

--host is used to indicate where the built binaries are intended
to run, while --build indicates the platform where the configure
script is being run and where it is built.

krichter722/vlc,vlc-mirror/vlc,jomanmuk/vlc-2.2,krichter722/vlc,shyamalschandra/vlc,vlc-mirror/vlc,shyamalschandra/vlc,vlc-mirror/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,xkfz007/vlc,shyamalschandra/vlc,krichter722/vlc,shyamalschandra/vlc,xkfz007/vlc,vlc-mirror/vlc,xkfz007/vlc,shyamalschandra/vlc,xkfz007/vlc,krichter722/vlc,vlc-mirror/vlc,jomanmuk/vlc-2.2,krichter722/vlc,krichter722/vlc,vlc-mirror/vlc,xkfz007/vlc,jomanmuk/vlc-2.2,xkfz007/vlc,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,xkfz007/vlc,krichter722/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.2,shyamalschandra/vlc