switch xattr_handler->set() to passing dentry and inode separately

preparation for similar switch in ->setxattr() (see the next commit for
rationale).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/hfsplus/xattr.h b/fs/hfsplus/xattr.h
index d04ba6f..68f6b53 100644
--- a/fs/hfsplus/xattr.h
+++ b/fs/hfsplus/xattr.h
@@ -21,7 +21,7 @@
 int __hfsplus_setxattr(struct inode *inode, const char *name,
 			const void *value, size_t size, int flags);
 
-int hfsplus_setxattr(struct dentry *dentry, const char *name,
+int hfsplus_setxattr(struct inode *inode, const char *name,
 				   const void *value, size_t size, int flags,
 				   const char *prefix, size_t prefixlen);