serial: 8250_bcm2835aux: Add ACPI support

Add ACPI support to 8250_bcm2835aux driver. This makes it possible to
use the miniuart on the Raspberry Pi with the tianocore/edk2 UEFI
firmware.

Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220207232129.402882-1-athierry@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>