9p: Use V9FS_MAGIC in statfs

Use V9FS_MAGIC as the file system type while filling kernel statfs
strucutre instead of using host file system magic number. Also move
the definition of V9FS_MAGIC from v9fs.h to standard magic.h file.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/include/linux/magic.h b/include/linux/magic.h
index eb9800f..ff690d0 100644
--- a/include/linux/magic.h
+++ b/include/linux/magic.h
@@ -57,5 +57,6 @@
 
 #define DEVPTS_SUPER_MAGIC	0x1cd1
 #define SOCKFS_MAGIC		0x534F434B
+#define V9FS_MAGIC		0x01021997
 
 #endif /* __LINUX_MAGIC_H__ */