ath9k: Remove empty test condition

Just some code cleanup to remove an empty if clause.
Signed-off-by: NEduardo Abinader <eduardo.abinader@riverbed.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath9k/ar9003_eeprom.c

@@ -3202,8 +3202,7 @@ static int ar9300_compress_decision(struct ath_hw *ah,
 			it, length);
 		break;
 	case _CompressBlock:
-		if (reference == 0) {
-		} else {
+		if (reference != 0) {
 			eep = ar9003_eeprom_struct_find_by_id(reference);
 			if (eep == NULL) {
 				ath_dbg(common, EEPROM,