storaged: replace LOG_TO() macros with LOG()

Storaged always writes to the SYSTEM log, so instead of using
LOG_TO(), it can use the normal LOG() macros as long as it calls
InitLogging() with a default to the SYSTEM log.

Test: storaged writes to the SYSTEM log still
Change-Id: I47e63bc92d55f9b1262a67e3508601ddbd9edc87