mac80211: fix a regression in the minstrel_ht improvement patches

Signed-off-by: Felix Fietkau <nbd@nbd.name>

package/kernel/mac80211/patches/subsys/315-mac80211-minstrel_ht-fix-infinite-loop-because-suppo.patch

@@ -0,0 +1,25 @@
+From: Colin Ian King <colin.king@canonical.com>
+Date: Thu, 22 Aug 2019 13:20:34 +0100
+Subject: [PATCH] mac80211: minstrel_ht: fix infinite loop because supported is
+ not being shifted
+
+Currently the for-loop will spin forever if variable supported is
+non-zero because supported is never changed.  Fix this by adding in
+the missing right shift of supported.
+
+Addresses-Coverity: ("Infinite loop")
+Fixes: 48cb39522a9d ("mac80211: minstrel_ht: improve rate probing for devices with static fallback")
+Signed-off-by: Colin Ian King <colin.king@canonical.com>
+---
+
+--- a/net/mac80211/rc80211_minstrel_ht.c
++++ b/net/mac80211/rc80211_minstrel_ht.c
+@@ -634,7 +634,7 @@ minstrel_ht_rate_sample_switch(struct mi
+ 		u16 supported = mi->supported[g_idx];
+ 
+ 		supported >>= mi->max_tp_rate[0] % MCS_GROUP_RATES;
+-		for (i = 0; supported; i++) {
++		for (i = 0; supported; supported >>= 1, i++) {
+ 			if (!(supported & 1))
+ 				continue;
+