UBUNTU: SAUCE: arm64: arch_timer: Move clocksource_counter and co around

UBUNTU: SAUCE: arm64: arch_timer: Move clocksource_counter and co around

BugLink: https://bugs.launchpad.net/bugs/1675509
In order to access clocksource_counter from the errata handling code,
move it (together with the related structures and functions) towards
the top of the file.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
(backported from commit d610f30af30c621399d2e7f5111ddc695f74311b
 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>