rtlwifi: Fix unitialized variable warnings

In http://lkml.indiana.edu/hypermail/linux/kernel/1104.1/01955.html, Geerti
Uytterhoeven reports the following warnings for the rtlwifi drivers.

src/drivers/net/wireless/rtlwifi/rtl8192c/dm_common.c: warning:
	 'cck_index' may be used uninitialized in this function: => 637
src/drivers/net/wireless/rtlwifi/rtl8192c/dm_common.c: warning:
	 'cck_index_old' may be used uninitialized in this function: => 637
src/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c: warning:
	 'box_extreg' may be used uninitialized in this function: => 303
src/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c: warning:
	 'box_reg' may be used uninitialized in this function: => 303
src/drivers/net/wireless/rtlwifi/rtl8192ce/rf.c: warning:
	 'chnlgroup' may be used uninitialized in this function: => 205
src/drivers/net/wireless/rtlwifi/rtl8192ce/rf.c: warning:
	 'u4_regvalue' may be used uninitialized in this function: => 450
src/drivers/net/wireless/rtlwifi/rtl8192cu/hw.c: warning:
	 'hq_sele' may be used uninitialized in this function: => 924

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c b/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
index f107660..bc9d241 100644
--- a/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
+++ b/drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
@@ -293,7 +293,7 @@
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
 	u8 boxnum;
-	u16 box_reg, box_extreg;
+	u16 box_reg = 0, box_extreg = 0;
 	u8 u1b_tmp;
 	bool isfw_read = false;
 	bool bwrite_sucess = false;