mcux: add Kconfig to configure NXP BLE monolithic feature

The monolithic feature allows to link the binary blobs with
the application during the build.

Signed-off-by: Axel Le Bourhis <axel.lebourhis@nxp.com>
Signed-off-by: Yassine El Aissaoui <yassine.elaissaoui@nxp.com>