Squashfs: fix function prototype

The fourth argument should be unsigned.  Also add missing include
so that the function prototype is defined in xattr_id.c

This fixes a couple of sparse warnings.
Signed-off-by: NPhillip Lougher <phillip@lougher.demon.co.uk>

fs/squashfs/xattr.h

@@ -25,7 +25,7 @@
 extern __le64 *squashfs_read_xattr_id_table(struct super_block *, u64,
 		u64 *, int *);
 extern int squashfs_xattr_lookup(struct super_block *, unsigned int, int *,
-		int *, unsigned long long *);
+		unsigned int *, unsigned long long *);
 #else
 static inline __le64 *squashfs_read_xattr_id_table(struct super_block *sb,
 		u64 start, u64 *xattr_table_start, int *xattr_ids)
@@ -35,7 +35,7 @@ static inline __le64 *squashfs_read_xattr_id_table(struct super_block *sb,
 }
 
 static inline int squashfs_xattr_lookup(struct super_block *sb,
-		unsigned int index, int *count, int *size,
+		unsigned int index, int *count, unsigned int *size,
 		unsigned long long *xattr)
 {
 	return 0;

fs/squashfs/xattr_id.c

@@ -34,6 +34,7 @@
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
+#include "xattr.h"
 
 /*
  * Map xattr id using the xattr id look up table