Merge "Adds option to read ROTPK from registers for FVP" into integration

docs/design/trusted-board-boot-build.rst

docs/getting_started/build-options.rst

docs/plat/arm/arm-build-options.rst

include/plat/arm/common/arm_def.h

include/plat/arm/common/plat_arm.h

plat/arm/board/common/board_arm_trusted_boot.c

plat/arm/board/common/board_common.mk

plat/arm/board/common/rotpk/arm_dev_rotpk.S

plat/arm/board/fvp/fvp_trusted_boot.c

plat/arm/board/fvp/platform.mk

plat/arm/board/juno/juno_trusted_boot.c

plat/arm/board/juno/platform.mk

plat/arm/board/rde1edge/platform.mk

plat/arm/board/rde1edge/rde1edge_trusted_boot.c

plat/arm/board/rdn1edge/platform.mk

plat/arm/board/rdn1edge/rdn1edge_trusted_boot.c

plat/arm/board/sgi575/platform.mk

plat/arm/board/sgi575/sgi575_trusted_boot.c

plat/arm/board/sgm775/platform.mk

plat/arm/board/sgm775/sgm775_trusted_boot.c