arm64: futex: ensure .fixup entries are sufficiently aligned

AArch64 instructions must be 4-byte aligned, so make sure this is true
for the futex .fixup section.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Git-commit: 4da7a56c59f28e27e8dcff61b5d7b05f6e203606
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Ian Maund <imaund@codeaurora.org>