msm: timer: Remove timer jumpback workaround on 8x30

The timer hardware on 8x30 does not experience the bug seen on other
A-family chips where the timer count will jump back from time to time.
So, remove the workaround for better performance. Additionally, drop
support for the now unsupported 8064 rumi.

Change-Id: Ie7d4f2a2b0c8c42e96cb87e7124d3aff76dc8ded
Signed-off-by: Jeff Ohlstein <johlstei@codeaurora.org>