arm64: enable generic CPU feature modalias matching for this architecture

arm64: enable generic CPU feature modalias matching for this architecture

This enables support for the generic CPU feature modalias implementation that
wires up optional CPU features to udev based module autoprobing.

A file <asm/cpufeature.h> is provided that maps CPU feature numbers to
elf_hwcap bits, which is the standard way on arm64 to advertise optional CPU
features both internally and to user space.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[catalin.marinas@arm.com: removed unnecessary "!!"]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 3be1a5c4f75989cf457f13f38ff0913dff6d4996)
Signed-off-by: Mark Brown <broonie@linaro.org>
Conflicts:
	arch/arm64/Kconfig