feat(ethos-n)!: load NPU firmware at BL2

feat(ethos-n)!: load NPU firmware at BL2

BL2 on Juno now loads the Arm(R) Ethos(TM)-N NPU firmware into a fixed
address, using the existing image loading framework.

Includes support for TRUSTED_BOARD_BOOT, if enabled, using the firmware
content and key certificates from the FIP.

Supports the ARM_IO_IN_DTB option so can specify the firmware location
from the dtb rather than it being hardcoded to the FIP

Update makefile to automatically embed the appropriate images into the
FIP.

BREAKING CHANGE: Building the FIP when TZMP1 support is enabled in the
NPU driver now requires a parameter to specify the NPU firmware file.

Signed-off-by: Rob Hughes <robert.hughes@arm.com>
Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>
Change-Id: I8cd64fb20d58f8bd539facb085606213d6cead06