ARM: 7323/1: Do not allow ARM_LPAE on pre-ARMv7 architectures

This patch expands the Kconfig dependencies for ARM_LPAE to not allow
enabling when architectures other than ARMv7 are built into the kernel.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>