Add AID_QCOM_DIAG/qcom_diag (initial value)

Add new AID AID_QCOM_DIAG for access control to /dev/diag.  The
number ID value is changed to be within the OEM range.

Note that this value deviated from past AID_QCOM_DIAG value, so
will be a problem for OTA.

Todo:
- The previous AID_QCOM_DIAG value is used by a new AOSP AID so
  there is a conflict.  Need to investigate the possibility of
  moving the new AOSP AID out for OTA-type scenario
- Create/use mechanism to inject new AID's to the system without
  changing the default AOSP definition file.  The current mechanism
  exists only for fs_config but not actual system ID's.

Change-Id: Ie286596a2e305a2bf188b658512e87cbea9b935c