Bluetooth: controller: Fix compilation error due to missing includes

When CONFIG_ARM_MPU is explicitly unset in application prj.conf there
were build warnings related with implicit declarations of following
symbols: NRF_DT_GPIOS_TO_PSEL, __WFE, __SEV.
Lack of NRF_DT_GPIOS_TO_PSEL lead to build error due to undeclared
dfegpio0_gpios symbol.

The cause for the warnings and error were missing soc.h includes in
few source files. The missing includes were added in this commit.

Signed-off-by: Piotr Pryga <piotr.pryga@nordicsemi.no>