net: UDP packet reply callback was losing net_buf
net: UDP packet reply callback was losing net_buf

UDP reply handler was not freeing net_buf properly if the
context was not passed properly to the callback. This
happened because the callback user data pointer was having
incorrect value.

Change-Id: Idfefd37b29674129252aa8f903fa9fe55de191cb
Signed-off-by: Jukka Rissanen <f9f077d1da4c7aa947f9864fa5a28c3588f6a45d@linux.intel.com>

finikorg/zephyr,finikorg/zephyr,fractalclone/zephyr-riscv,mirzak/zephyr-os,aceofall/zephyr-iotos,pklazy/zephyr,32bitmicro/zephyr,punitvara/zephyr,fractalclone/zephyr-riscv,aceofall/zephyr-iotos,mbolivar/zephyr,zephyriot/zephyr,bboozzoo/zephyr,pklazy/zephyr,runchip/zephyr-cc3220,zephyriot/zephyr,bboozzoo/zephyr,runchip/zephyr-cc3200,fractalclone/zephyr-riscv,tidyjiang8/zephyr-doc,runchip/zephyr-cc3220,zephyriot/zephyr,nashif/zephyr,tidyjiang8/zephyr-doc,nashif/zephyr,GiulianoFranchetto/zephyr,holtmann/zephyr,sharronliu/zephyr,coldnew/zephyr-project-fork,bigdinotech/zephyr,runchip/zephyr-cc3220,Vudentz/zephyr,bigdinotech/zephyr,32bitmicro/zephyr,32bitmicro/zephyr,finikorg/zephyr,mirzak/zephyr-os,coldnew/zephyr-project-fork,coldnew/zephyr-project-fork,zephyriot/zephyr,bboozzoo/zephyr,GiulianoFranchetto/zephyr,rsalveti/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,erwango/zephyr,sharronliu/zephyr,coldnew/zephyr-project-fork,bigdinotech/zephyr,runchip/zephyr-cc3200,jamesonwilliams/zephyr-kernel,rsalveti/zephyr,ldts/zephyr,runchip/zephyr-cc3200,sharronliu/zephyr,erwango/zephyr,jamesonwilliams/zephyr-kernel,Vudentz/zephyr,tidyjiang8/zephyr-doc,mirzak/zephyr-os,Vudentz/zephyr,bboozzoo/zephyr,kraj/zephyr,kraj/zephyr,holtmann/zephyr,explora26/zephyr,fbsder/zephyr,pklazy/zephyr,jamesonwilliams/zephyr-kernel,explora26/zephyr,zephyrproject-rtos/zephyr,fractalclone/zephyr-riscv,ldts/zephyr,fbsder/zephyr,erwango/zephyr,rsalveti/zephyr,mbolivar/zephyr,explora26/zephyr,jamesonwilliams/zephyr-kernel,erwango/zephyr,holtmann/zephyr,galak/zephyr,finikorg/zephyr,runchip/zephyr-cc3200,zephyrproject-rtos/zephyr,32bitmicro/zephyr,kraj/zephyr,explora26/zephyr,mirzak/zephyr-os,fractalclone/zephyr-riscv,GiulianoFranchetto/zephyr,jamesonwilliams/zephyr-kernel,fbsder/zephyr,runchip/zephyr-cc3220,fbsder/zephyr,punitvara/zephyr,holtmann/zephyr,holtmann/zephyr,runchip/zephyr-cc3220,ldts/zephyr,ldts/zephyr,pklazy/zephyr,mirzak/zephyr-os,sharronliu/zephyr,nashif/zephyr,rsalveti/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,bboozzoo/zephyr,kraj/zephyr,zephyrproject-rtos/zephyr,aceofall/zephyr-iotos,nashif/zephyr,fbsder/zephyr,bigdinotech/zephyr,punitvara/zephyr,finikorg/zephyr,sharronliu/zephyr,punitvara/zephyr,galak/zephyr,tidyjiang8/zephyr-doc,kraj/zephyr,aceofall/zephyr-iotos,zephyriot/zephyr,tidyjiang8/zephyr-doc,bigdinotech/zephyr,pklazy/zephyr,32bitmicro/zephyr,zephyrproject-rtos/zephyr,coldnew/zephyr-project-fork,galak/zephyr,mbolivar/zephyr,mbolivar/zephyr,mbolivar/zephyr,Vudentz/zephyr,galak/zephyr,nashif/zephyr,Vudentz/zephyr,aceofall/zephyr-iotos,Vudentz/zephyr,runchip/zephyr-cc3200,zephyrproject-rtos/zephyr,erwango/zephyr,galak/zephyr,punitvara/zephyr,rsalveti/zephyr