msm: timer: compensate for timer shift in msm_read_timer_count

Some msm targets have timers whose lower bits are unreliable. So, we
present our timers as lower frequency than they actually are, and ignore
the bottom 5 bits on such targets. This compensation was erroneously
removed from the msm_read_timer_count function, so restore it.

This was broken by 94790ec2 "msm: timer: SMP timer support for msm".

Signed-off-by: Jeff Ohlstein <johlstei@codeaurora.org>