Clean up VHT override max A-MPDU override calculation

There is no need to use runtime call to find_first_bit() to determine
shift amount for a constant integer.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/common/ieee802_11_defs.h

@@ -833,6 +833,7 @@ struct ieee80211_ampe_ie {
 #define VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_6        ((u32) BIT(24) | BIT(25))
 #define VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX      ((u32) BIT(23) | \
 							   BIT(24) | BIT(25))
+#define VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX_SHIFT 23
 #define VHT_CAP_VHT_LINK_ADAPTATION_VHT_UNSOL_MFB   ((u32) BIT(27))
 #define VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB     ((u32) BIT(26) | BIT(27))
 #define VHT_CAP_RX_ANTENNA_PATTERN                  ((u32) BIT(28))

wpa_supplicant/wpa_supplicant.c

@@ -3204,10 +3204,6 @@ void wpa_supplicant_apply_vht_overrides(
 {
 	struct ieee80211_vht_capabilities *vhtcaps;
 	struct ieee80211_vht_capabilities *vhtcaps_mask;
-#ifdef CONFIG_HT_OVERRIDES
-	int max_ampdu;
-	const u32 max_ampdu_mask = VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX;
-#endif /* CONFIG_HT_OVERRIDES */
 
 	if (!ssid)
 		return;
@@ -3225,9 +3221,12 @@ void wpa_supplicant_apply_vht_overrides(
 
 #ifdef CONFIG_HT_OVERRIDES
 	/* if max ampdu is <= 3, we have to make the HT cap the same */
-	if (ssid->vht_capa_mask & max_ampdu_mask) {
-		max_ampdu = (ssid->vht_capa & max_ampdu_mask) >>
-			find_first_bit(max_ampdu_mask);
+	if (ssid->vht_capa_mask & VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX) {
+		int max_ampdu;
+
+		max_ampdu = (ssid->vht_capa &
+			     VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX) >>
+			VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MAX_SHIFT;
 
 		max_ampdu = max_ampdu < 3 ? max_ampdu : 3;
 		wpa_set_ampdu_factor(wpa_s,