net: lwm2m: remove silent fail for bad endpoint data in rd_client
net: lwm2m: remove silent fail for bad endpoint data in rd_client

The next error check is much more suitable to handle the error due to
the error message which lets the user know that something went wrong.

Fixes #7661.

Signed-off-by: Daniel Egger <3d0f3b9ddcacec30c4008c5e030e6c13a478cb4f@eggers-club.de>

mbolivar/zephyr,nashif/zephyr,zephyriot/zephyr,mbolivar/zephyr,kraj/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,GiulianoFranchetto/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,nashif/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,explora26/zephyr,galak/zephyr,nashif/zephyr,ldts/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,Vudentz/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,finikorg/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,mbolivar/zephyr,mbolivar/zephyr,zephyriot/zephyr,galak/zephyr,Vudentz/zephyr,ldts/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,zephyriot/zephyr,nashif/zephyr,ldts/zephyr,punitvara/zephyr,explora26/zephyr,Vudentz/zephyr,punitvara/zephyr,kraj/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,zephyriot/zephyr,Vudentz/zephyr,kraj/zephyr,zephyriot/zephyr,kraj/zephyr,ldts/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,explora26/zephyr,punitvara/zephyr,kraj/zephyr,zephyrproject-rtos/zephyr