loapic_intr: factor (out) APIC accesses in static functions
loapic_intr: factor (out) APIC accesses in static functions

This will accomodate newer access models later, with variations of those
functions' contents.

Signed-off-by: Gustavo Lima Chaves <dc5f5719afbf9af3fe162a3ac398146b4d0a4afe@intel.com>

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