msm_serial_hs_lite: Restore using "no_log" readl/writel variants

msm_hsl_read and msm_hsl_write are called frequently enough to flood
the RTB logs with readl/writel events. Restore using _no_log variants
of those accessors to make RTB log useful for debugging.

Change-Id: Idf05034a847d53a7df38e654c464a94f78130a35
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>