ath9k_hw: fix an off-by-one error in the PDADC boundaries calculation

PDADC values were only generated for values surrounding the target
index, however not for the target index itself, leading to a minor
error in the generated curve.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/eeprom_def.c b/drivers/net/wireless/ath/ath9k/eeprom_def.c
index 60480a1..02e6c2a 100644
--- a/drivers/net/wireless/ath/ath9k/eeprom_def.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom_def.c
@@ -730,7 +730,7 @@
 				    vpdTableI[i][sizeCurrVpdTable - 2]);
 		vpdStep = (int16_t)((vpdStep < 1) ? 1 : vpdStep);
 
-		if (tgtIndex > maxIndex) {
+		if (tgtIndex >= maxIndex) {
 			while ((ss <= tgtIndex) &&
 			       (k < (AR5416_NUM_PDADC_VALUES - 1))) {
 				tmpVal = (int16_t)((vpdTableI[i][sizeCurrVpdTable - 1] +