BugLink: https://bugs.launchpad.net/bugs/1848780

commit ff96f7bc usptream

Use the appropriate accessor for the feature bit by keeping
track of the sign of the feature.

This is a pre-requisite for the commit 28c5dcb2 upstream,
which fixes the arm64_ftr_value() for signed feature fields.

Cc: stable@vger.kernel.org # v4.4
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>