Add build and run configs to exercise ARM_LINUX_KERNEL_AS_BL33 feature

This patch also adds test configurations that boot Linux kernel
directly without a normal world bootloader such as U-Boot

Refer to the following patches which fix the false dependency of
ARM_LINUX_KERNEL_AS_BL33 on RESET_TO_BL31 feature:

https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/8353
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/8352

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: I2eb1dfcc3ee6b4417a887c0bd3840f3d9da20dd0
8 files changed