Revert "arm64: Introduce execute-only page access permissions"

This reverts commit f72129c2.

While the aim is increased security for --x memory maps, it does not
protect against kernel level reads. Until SECCOMP is implemented for
arm64, revert this patch to avoid giving a false idea of execute-only
mappings.

Change-Id: Ifb2fb182450bc656189738842f344f63daa5e317
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Git-commit:5a0fdfada3a2aa50d7b947a2e958bf00cbe0d830
Git-repo: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git


Signed-off-by: Ravi Kumar Siddojigari <rsiddoji@codeaurora.org>