clocksource: arm_arch_timer: Enable counter access for 32-bit ARM

clocksource: arm_arch_timer: Enable counter access for 32-bit ARM

The only difference between arm and arm64's implementations of
arch_counter_set_user_access is that 32-bit ARM does not enable user
access to the virtual counter.  We want to enable this access for the
32-bit ARM VDSO, so copy the arm64 version to the driver itself, and
remove the arch-specific implementations.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
(cherry picked from commit 8b8dde00347ef409b29abd97e5833ffdb4ed7508)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>