Modify PMLOG_TRACE

:Release Notes:
Now, macro PMLOG_TRACE records the log to mainstream.

:Detailed Notes:
Originally, PMLOG_TRACE had recorded the log to legacy-log file.
It will use macro PmLogDebug now so that will be recorded to
messages file.

:Testing Performed:
Compiled locally and tested on locally.
Verified in the log file, properly displayed in /var/log/messages.

:QA Notes:

:Issues Addressed:
[GF-9505] pmloglib: Use the new API for PMLOG_TRACE

Open-webOS-DCO-1.0-Signed-off-by: Hongjeon Ha <hj.ha@lge.com>

Change-Id: Id18f172db546ca4384fa62cbed68cf7dd0ecf744
Reviewed-on: https://g2g.palm.com/2873
Reviewed-by: Hongjeon Ha <hj.ha@lge.com>
Tested-by: Hongjeon Ha <hj.ha@lge.com>
Reviewed-by: Build Verification
Reviewed-by: Gayathri Srinivasan <gayathri.srinivasan@lge.com>