cfg80211: clean up variable use in cfg80211_parse_colocated_ap()

The "ap_info->tbtt_info_len" and "length" variables are the same value
but it is confusing how the names are mixed up.  Let's use "length"
everywhere for consistency.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YJaMNzZENkYFAYQX@mwandaSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/scan.c

@@ -618,7 +618,7 @@ static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
 
 		freq = ieee80211_channel_to_frequency(ap_info->channel, band);
 
-		if (end - pos < count * ap_info->tbtt_info_len)
+		if (end - pos < count * length)
 			break;
 
 		/*
@@ -630,7 +630,7 @@ static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
 		if (band != NL80211_BAND_6GHZ ||
 		    (length != IEEE80211_TBTT_INFO_OFFSET_BSSID_BSS_PARAM &&
 		     length < IEEE80211_TBTT_INFO_OFFSET_BSSID_SSSID_BSS_PARAM)) {
-			pos += count * ap_info->tbtt_info_len;
+			pos += count * length;
 			continue;
 		}
 
@@ -653,7 +653,7 @@ static int cfg80211_parse_colocated_ap(const struct cfg80211_bss_ies *ies,
 				kfree(entry);
 			}
 
-			pos += ap_info->tbtt_info_len;
+			pos += length;
 		}
 	}