net: gptp: Make sure that neighbor_rate_ratio cannot be 0
net: gptp: Make sure that neighbor_rate_ratio cannot be 0

Neighbor rate ratio cannot be 0 as that would mean 0 packet
delivery time which is not plausible.
Add also some debugging to print current neighbor propagation
delay value.

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

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