Bluetooth: Mesh: Add read callback for ccc in provisioning service
Bluetooth: Mesh: Add read callback for ccc in provisioning service

This patch adds read permission for client characteristic configuration
descriptor. This is required by MESH/NODE/MPS/BV-06-C,
MESH/NODE/MPS/BV-07-C PTS tests.

Signed-off-by: Grzegorz Kolodziejczyk <e2939bdb4227a060339d47f1edd062ee591694cc@codecoup.pl>

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