9p: Reduce object size with CONFIG_NET_9P_DEBUG

Reduce object size by deduplicating formats.

Use vsprintf extension %pV.
Rename P9_DPRINTK uses to p9_debug, align arguments.
Add function for _p9_debug and macro to add __func__.
Add missing "\n"s to p9_debug uses.
Remove embedded function names as p9_debug adds it.
Remove P9_EPRINTK macro and convert use to pr_<level>.
Add and use pr_fmt and pr_<level>.

$ size fs/9p/built-in.o*
   text	   data	    bss	    dec	    hex	filename
  62133	    984	  16000	  79117	  1350d	fs/9p/built-in.o.new
  67342	    984	  16928	  85254	  14d06	fs/9p/built-in.o.old
$ size net/9p/built-in.o*
   text	   data	    bss	    dec	    hex	filename
  88792	   4148	  22024	 114964	  1c114	net/9p/built-in.o.new
  94072	   4148	  23232	 121452	  1da6c	net/9p/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index c70251d..06d19735 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -121,7 +121,7 @@
 	struct p9_fid *fid;
 	int retval = 0;
 
-	P9_DPRINTK(P9_DEBUG_VFS, " \n");
+	p9_debug(P9_DEBUG_VFS, "\n");
 
 	v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
 	if (!v9ses)
@@ -191,7 +191,7 @@
 		goto release_sb;
 	v9fs_fid_add(root, fid);
 
-	P9_DPRINTK(P9_DEBUG_VFS, " simple set mount, return 0\n");
+	p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n");
 	return dget(sb->s_root);
 
 clunk_fid:
@@ -223,7 +223,7 @@
 {
 	struct v9fs_session_info *v9ses = s->s_fs_info;
 
-	P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s);
+	p9_debug(P9_DEBUG_VFS, " %p\n", s);
 
 	kill_anon_super(s);
 
@@ -231,7 +231,7 @@
 	v9fs_session_close(v9ses);
 	kfree(v9ses);
 	s->s_fs_info = NULL;
-	P9_DPRINTK(P9_DEBUG_VFS, "exiting kill_super\n");
+	p9_debug(P9_DEBUG_VFS, "exiting kill_super\n");
 }
 
 static void
@@ -303,7 +303,7 @@
 	 * send an fsync request to server irrespective of
 	 * wbc->sync_mode.
 	 */
-	P9_DPRINTK(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
 	v9inode = V9FS_I(inode);
 	if (!v9inode->writeback_fid)
 		return 0;
@@ -326,7 +326,7 @@
 	 * send an fsync request to server irrespective of
 	 * wbc->sync_mode.
 	 */
-	P9_DPRINTK(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
+	p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode);
 	v9inode = V9FS_I(inode);
 	if (!v9inode->writeback_fid)
 		return 0;