wifi: rtw89: Remove the redundant else branch in the function rtw89_phy_get_kpath

The assignment of the else and if branches is the same in the "case:
MLO_2_PLUS_0_1RF" branch of the function rtw89_phy_get_kpath, so we
remove it and add comments here to make the code easier to understand.

./drivers/net/wireless/realtek/rtw89/phy.c:6406:2-4: WARNING: possible condition with no effect (if == else).
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=8812Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://msgid.link/20240422072922.50940-1-jiapeng.chong@linux.alibaba.com

drivers/net/wireless/realtek/rtw89/phy.c

@@ -6403,10 +6403,8 @@ enum rtw89_rf_path_bit rtw89_phy_get_kpath(struct rtw89_dev *rtwdev,
 			return RF_D;
 	case MLO_0_PLUS_2_1RF:
 	case MLO_2_PLUS_0_1RF:
-		if (phy_idx == RTW89_PHY_0)
-			return RF_AB;
-		else
-			return RF_AB;
+		/* for both PHY 0/1 */
+		return RF_AB;
 	case MLO_0_PLUS_2_2RF:
 	case MLO_2_PLUS_0_2RF:
 	case MLO_2_PLUS_2_2RF: