[L] Change in coreboot[main]: mb/arm/rdn2: Add support for Arm Neoverse N2

[Naresh Solanki (Code Review)]

Attention is currently required from: Angel Pons, Arthur Heymans, David Milosevic, Maximilian Brune, Patrick Rudolph, Paul Menzel.

Naresh Solanki has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79103?usp=email )

Change subject: mb/arm/rdn2: Add support for Arm Neoverse N2
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Patch Set 3:

(2 comments)

File src/mainboard/arm/rdn2/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/79103/comment/6800a498_c2da40c5 :
PS3, Line 15: mcmodel=large
> This really looks like a CFLAG and not a CPPFLAG. […]

These aren't needed & should have being removed as part of cleanup.

https://review.coreboot.org/c/coreboot/+/79103/comment/b6f3efc2_05f12ee4 :
PS3, Line 16: CPPFLAGS_common += -mstrict-align
> This is a CFLAG. […]

Was facing data abort & hence these were added. But it didn't help & resolved by fixing page attribute for FLASH address range.  Hence will be removed this.