mac80211: merge value scaling macros of minstrel_ht and minstrel

Both minstrel versions use individual ways to scale up integer values
to perform calculations. Merge minstrel_ht's scaling macros into
minstrels header file and use them in both minstrel versions.

Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
index d5a5622..c0ebfac 100644
--- a/net/mac80211/rc80211_minstrel_debugfs.c
+++ b/net/mac80211/rc80211_minstrel_debugfs.c
@@ -79,9 +79,9 @@
 		p += sprintf(p, "%3u%s", mr->bitrate / 2,
 				(mr->bitrate & 1 ? ".5" : "  "));
 
-		tp = mr->cur_tp / ((18000 << 10) / 96);
-		prob = mr->cur_prob / 18;
-		eprob = mr->probability / 18;
+		tp = MINSTREL_TRUNC(mr->cur_tp / 10);
+		prob = MINSTREL_TRUNC(mr->cur_prob * 1000);
+		eprob = MINSTREL_TRUNC(mr->probability * 1000);
 
 		p += sprintf(p, "  %6u.%1u   %6u.%1u   %6u.%1u        "
 				"%3u(%3u)   %8llu    %8llu\n",