rtlwifi: rtl8192c: Add new definitions in the dm_common header

Changes in the gain-control mechanism will require some changes in the header.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>