mac80211: Fix warning in minstrel rate control

When compiling the minstrel rate-control code on x86_64 architecture, the following warning is issued:

CC [M] net/mac80211/rc80211_minstrel_debugfs.o
net/mac80211/rc80211_minstrel_debugfs.c:145: warning: initialization from incompatible pointer type

The fix requires changing the type of minstrel_stats_read().

---

John,

This warning also prints in mainline - this belongs in 2.6.28.

Larry
---

Index: linux-2.6/net/mac80211/rc80211_minstrel_debugfs.c
===================================================================
@@ -106,7 +106,7 @@ minstrel_stats_open(struct inode *inode,
 	return 0;
 }
 
-static int
+static ssize_t
 minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *o)
 {
 	struct minstrel_stats_info *ms;