Bluetooth: controller: Fix first interval to be within +/-16us
Bluetooth: controller: Fix first interval to be within +/-16us

Due to the missing remainder support in the ticker_start
function for first interval, fix implementation so as to
round the first interval/offset during master connection
setup and connection update to within +/-16us.

Signed-off-by: Vinayak Kariappa Chettimada <e780c9f87dc729ad454f47292ad82c8652353064@nordicsemi.no>

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