net: trickle: Do clock wrap check properly
net: trickle: Do clock wrap check properly

No need to complex overflow checks that are error prone.
Coverity complained that the original diff check was always
false.

Coverity-CID: 173639

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

rsalveti/zephyr,zephyriot/zephyr,fbsder/zephyr,rsalveti/zephyr,aceofall/zephyr-iotos,fbsder/zephyr,nashif/zephyr,kraj/zephyr,rsalveti/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,runchip/zephyr-cc3220,GiulianoFranchetto/zephyr,mbolivar/zephyr,nashif/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,mbolivar/zephyr,explora26/zephyr,Vudentz/zephyr,punitvara/zephyr,explora26/zephyr,fbsder/zephyr,finikorg/zephyr,zephyriot/zephyr,runchip/zephyr-cc3220,explora26/zephyr,GiulianoFranchetto/zephyr,kraj/zephyr,Vudentz/zephyr,fbsder/zephyr,Vudentz/zephyr,aceofall/zephyr-iotos,zephyriot/zephyr,aceofall/zephyr-iotos,mbolivar/zephyr,aceofall/zephyr-iotos,Vudentz/zephyr,finikorg/zephyr,ldts/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,fbsder/zephyr,kraj/zephyr,kraj/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,finikorg/zephyr,rsalveti/zephyr,zephyriot/zephyr,punitvara/zephyr,galak/zephyr,runchip/zephyr-cc3220,zephyrproject-rtos/zephyr,kraj/zephyr,punitvara/zephyr,nashif/zephyr,ldts/zephyr,galak/zephyr,aceofall/zephyr-iotos,nashif/zephyr,mbolivar/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,runchip/zephyr-cc3220,ldts/zephyr,explora26/zephyr,mbolivar/zephyr,runchip/zephyr-cc3220,rsalveti/zephyr,nashif/zephyr,galak/zephyr,galak/zephyr,zephyriot/zephyr,Vudentz/zephyr,explora26/zephyr