FROMLIST: arm64: Kconfig: Add CONFIG_UNMAP_KERNEL_AT_EL0

Add a Kconfig entry to control use of the entry trampoline, which allows
us to unmap the kernel whilst running in userspace and improve the
robustness of KASLR.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Tested-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
(cherry picked from git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git


 commit 084eb77cd3a81134d02500977dc0ecc9277dc97d)
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Change-Id: Iff788c61b8a993088ed41d6251363e767dfa4e71
Git-Commit: 3ec3abcb
Git-repo: git://android.googlesource.com/kernel/common.git


Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>