msm_rtb: Don't lose the __user tag on relaxed reads/writes

The RTB logging was accidently losing the __user tag from I/O operation
addresses which caused the static analysis tools to be upset. Force a
void * address for the logger but leave the original address untouched for
the actual operation.

Change-Id: Ic0dedbad38a49d6bfd9e102f91bbf9ae21c4c14c
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>