feat(s32g274a): add S32G274ARDB2 board support

S32G274ARDB2 is a development board to showcase the capabilities of the
S32G2 SoC. It includes 4 ARM Cortex-A53 cores running at 1.0GHz, 4GBs
of DDR, accelerators for automotive networking and many other
peripherals.

The added support is minimal and only includes the BL2 stage, with no
MMU enabled. The FIP is preloaded by the BootROM in SRAM, and BL2 copies
BL31 and BL33 from FIP to their designated addresses.

Change-Id: Iedda23302768ab70d63787117c5f6f3c21eb9842
Signed-off-by: Bogdan Hamciuc <bogdan.hamciuc@nxp.com>
Signed-off-by: Dan Nica <dan.nica@nxp.com>
Signed-off-by: Andra-Teodora Ilie <andra.ilie@nxp.com>
Signed-off-by: Bogdan Roman <bogdan-gabriel.roman@nxp.com>
Signed-off-by: Ghennadi Procopciuc <ghennadi.procopciuc@nxp.com>