UBUNTU: SAUCE: arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled

UBUNTU: SAUCE: arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled

BugLink: https://bugs.launchpad.net/bugs/1675509
Userspace being allowed to use read CNTVCT_EL0 anytime (and not
only in the VDSO), we need to enable trapping whenever a cntvct
workaround is enabled on a given CPU.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(cherry picked from commit 13fbbd32946ac882cdd3f07c02687f6b860d1a7f
 in the timers/errata-rework branch of
 git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>