Saucy for ofono.

Approved by Ricardo Salveti, PS Jenkins bot.
[rilmodem] Re-factored debug tracing to simplify and add ifdef logic.
[rildmodem] More DBG cleanup.
[rilmodem] Get rid of un-used sim_debug() function.
[gril] Add conditional guards to DBG statements.
Re-merge from trunk.
[gril/rilmodem] More debug clean-up/re-factoring.
[rilmodem] Add trace code to sms and voicecall.
[rilmodem] Fix compile-time error...
[gril/rilmodem] Re-factored tracing code to enable/disable by env variable.
[rilmodem] Remove un-needed SMS hex tracing calls.
[gril/rilmodem] Make g_ril_append_print_buf conditional.
[ril/rilmodem] Minor cleanup.
[gril/rilmodem] Get rid of tracing start/stop request/response #defines.
[gril/rilmodem] Add conditional build-time logic to RIL command tracing, and low-level gril logging.

Approved by Ricardo Salveti, PS Jenkins bot.