tty : msm_serial: Remove the rtb logs of msm_serial write and read

msm_write/read use write/read_relaxed function which will create
lots of RTB logging. Change the API to no_log version to remove
those RTB logs.

CRs-Fixed: 1062953
Change-Id: Id6524b7ae3e82e10ca651a2ca0de9223c18109da
Signed-off-by: Runmin Wang <runminw@codeaurora.org>