arm64: make SCTLR compat config depend on CONFIG_ARMV7_COMPAT

Conflicts:
	arch/arm64/mm/proc.S

Change-Id: I76e0067839c96e3082b42c80d3fc670cf3d371b5
Signed-off-by: Rich Wiley <rwiley@nvidia.com>
Reviewed-on: http://git-master/r/422173


GVS: Gerrit_Virtual_Submit
Reviewed-by: Alexander Van Brunt <avanbrunt@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Tested-by: Bharat Nihalani <bnihalani@nvidia.com>