staging: rtl8187se: Deleted rtl8225z2_rf_set_mode function

After the next warning messages by sparse tools:

drivers/staging/rtl8187se/r8180_rtl8225z2.c:609:6: warning: symbol 'rtl8225z2_rf_set_mode' was not declared. Should it be static?
drivers/staging/rtl8187se/r8180_rtl8225z2.c:609:13: warning: ‘rtl8225z2_rf_set_mode’ defined but not used [-Wunused-function]
 static void rtl8225z2_rf_set_mode(struct net_device *dev)

And the next search:
~/opw/dev/staging/drivers/staging/rtl8187se
 (staging-next) $ git grep rtl8225z2_rf_set_mode
r8180_rtl8225z2.c:void rtl8225z2_rf_set_mode(struct net_device *dev)

I decided to delete rtl8225z2_rf_set_mode function.

Signed-off-by: Ana Rey <anarey@gmail.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
diff --git a/drivers/staging/rtl8187se/r8180_rtl8225z2.c b/drivers/staging/rtl8187se/r8180_rtl8225z2.c
index 73a58d1..47104fa 100644
--- a/drivers/staging/rtl8187se/r8180_rtl8225z2.c
+++ b/drivers/staging/rtl8187se/r8180_rtl8225z2.c
@@ -606,45 +606,6 @@
 	rtl8225z2_rf_set_chan(dev, priv->chan);
 }
 
-void rtl8225z2_rf_set_mode(struct net_device *dev)
-{
-	struct r8180_priv *priv = ieee80211_priv(dev);
-
-	if (priv->ieee80211->mode == IEEE_A) {
-		write_rtl8225(dev, 0x5, 0x1865);
-		write_nic_dword(dev, RF_PARA, 0x10084);
-		write_nic_dword(dev, RF_TIMING, 0xa8008);
-		write_phy_ofdm(dev, 0x0, 0x0);
-		write_phy_ofdm(dev, 0xa, 0x6);
-		write_phy_ofdm(dev, 0xb, 0x99);
-		write_phy_ofdm(dev, 0xf, 0x20);
-		write_phy_ofdm(dev, 0x11, 0x7);
-
-		rtl8225z2_set_gain(dev, 4);
-
-		write_phy_ofdm(dev, 0x15, 0x40);
-		write_phy_ofdm(dev, 0x17, 0x40);
-
-		write_nic_dword(dev, 0x94, 0x10000000);
-	} else {
-		write_rtl8225(dev, 0x5, 0x1864);
-		write_nic_dword(dev, RF_PARA, 0x10044);
-		write_nic_dword(dev, RF_TIMING, 0xa8008);
-		write_phy_ofdm(dev, 0x0, 0x1);
-		write_phy_ofdm(dev, 0xa, 0x6);
-		write_phy_ofdm(dev, 0xb, 0x99);
-		write_phy_ofdm(dev, 0xf, 0x20);
-		write_phy_ofdm(dev, 0x11, 0x7);
-
-		rtl8225z2_set_gain(dev, 4);
-
-		write_phy_ofdm(dev, 0x15, 0x40);
-		write_phy_ofdm(dev, 0x17, 0x40);
-
-		write_nic_dword(dev, 0x94, 0x04000002);
-	}
-}
-
 #define MAX_DOZE_WAITING_TIMES_85B		20
 #define MAX_POLLING_24F_TIMES_87SE		10
 #define LPS_MAX_SLEEP_WAITING_TIMES_87SE	5