aemfvp-a-rme: Remove duplicate edk2setup

Move tf-a config flag into aemfvp config file

aemfvp-a-rme: Add fix for initrd naming

Add fix for initrd naming in grub.cfg for realm distro boot

Signed-off-by: Ben Taylor <ben.taylor@linaro.org>
Change-Id: Ic5af350c4c748f9fd24c7202df2ffd1a7221100b