armv8: ls2088aqds: Add TFABOOT support

TFABOOT support includes:
 - ls2088aqds_tfa_defconfig to be loaded by trusted firmware
 - environment address and size changes for TFABOOT

Signed-off-by: Pankit Garg <pankit.garg@nxp.com>
Signed-off-by: Ruchika Gupta <ruchika.gupta@nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>