arm64: add AT_HWCAP2 support for 32-bit compat

Add support for the ELF auxv entry AT_HWCAP2 when running 32-bit
ELF binaries in compat mode.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Git-commit: 28964d32d495a0753986d464c48c8e1ae73699be
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>