staging: rtl8188eu: re-use hex_to_bin() instead of custom code

hex_to_bin could be used to convert hexdecimal digit to its binary
representation.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: navin patidar <navin.patidar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/core/rtw_ieee80211.c

@@ -1067,23 +1067,6 @@ enum parse_res rtw_ieee802_11_parse_elems(u8 *start, uint len,
 	return unknown ? ParseUnknown : ParseOK;
 }
 
-u8 key_char2num(u8 ch)
-{
-	if ((ch >= '0') && (ch <= '9'))
-		return ch - '0';
-	else if ((ch >= 'a') && (ch <= 'f'))
-		return ch - 'a' + 10;
-	else if ((ch >= 'A') && (ch <= 'F'))
-		return ch - 'A' + 10;
-	else
-		return 0xff;
-}
-
-u8 str_2char2num(u8 hch, u8 lch)
-{
-    return (key_char2num(hch) * 10) + key_char2num(lch);
-}
-
 void rtw_macaddr_cfg(u8 *mac_addr)
 {
 	u8 mac[ETH_ALEN];

drivers/staging/rtl8188eu/include/wlan_bssdef.h

@@ -340,7 +340,4 @@ struct ndis_802_11_cap {
 	struct ndis_802_11_auth_encrypt AuthenticationEncryptionSupported[1];
 };
 
-u8 key_char2num(u8 ch);
-u8 str_2char2num(u8 hch, u8 lch);
-
 #endif /* ifndef WLAN_BSSDEF_H_ */

drivers/staging/rtl8188eu/os_dep/ioctl_linux.c

@@ -2697,7 +2697,7 @@ static int rtw_p2p_set_intent(struct net_device *dev,
 		intent = extra[0] - '0';
 		break;
 	case 2:
-		intent = str_2char2num(extra[0], extra[1]);
+		intent = hex_to_bin(extra[0]) * 10 + hex_to_bin(extra[1]);
 		break;
 	}
 	if (intent <= 15)
@@ -2722,7 +2722,7 @@ static int rtw_p2p_set_listen_ch(struct net_device *dev,
 		listen_ch = extra[0] - '0';
 		break;
 	case 2:
-		listen_ch = str_2char2num(extra[0], extra[1]);
+		listen_ch = hex_to_bin(extra[0]) * 10 + hex_to_bin(extra[1]);
 		break;
 	}
 
@@ -2755,7 +2755,7 @@ static int rtw_p2p_set_op_ch(struct net_device *dev,
 		op_ch = extra[0] - '0';
 		break;
 	case 2:
-		op_ch = str_2char2num(extra[0], extra[1]);
+		op_ch = hex_to_bin(extra[0]) * 10 + hex_to_bin(extra[1]);
 		break;
 	}