feat(plat/arm): add base ram error injection support

Add support to perform error injection on base ram. Implementation
added that programs AP secure ram ecc registers to inject 1-bit CE into
the non-secure base element ram.

This patch helps validate the firmware-first error handing support
implemented for base element rams.

Signed-off-by: Omkar Anand Kulkarni <omkar.kulkarni@arm.com>
Change-Id: Ief88ee71c05d891fb07848284bc0b1743e473996