nfs: define nfs_inc_fscache_stats and using it as possible

Define and use nfs_inc_fscache_stats when plus one, which can save to
pass one parameter.

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/iostat.h b/fs/nfs/iostat.h
index c583248..0cb806f 100644
--- a/fs/nfs/iostat.h
+++ b/fs/nfs/iostat.h
@@ -55,6 +55,11 @@
 {
 	this_cpu_add(NFS_SERVER(inode)->io_stats->fscache[stat], addend);
 }
+static inline void nfs_inc_fscache_stats(struct inode *inode,
+					 enum nfs_stat_fscachecounters stat)
+{
+	this_cpu_inc(NFS_SERVER(inode)->io_stats->fscache[stat]);
+}
 #endif
 
 static inline struct nfs_iostats __percpu *nfs_alloc_iostats(void)