usb/gadget: fix misannotations

__user * != * __user
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

drivers/usb/gadget/f_fs.c

@@ -340,7 +340,7 @@ ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
 
 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
 	__attribute__((warn_unused_result, nonnull));
-static char *ffs_prepare_buffer(const char * __user buf, size_t len)
+static char *ffs_prepare_buffer(const char __user *buf, size_t len)
 	__attribute__((warn_unused_result, nonnull));
 
 
@@ -2436,7 +2436,7 @@ static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
 		: mutex_lock_interruptible(mutex);
 }
 
-static char *ffs_prepare_buffer(const char * __user buf, size_t len)
+static char *ffs_prepare_buffer(const char __user *buf, size_t len)
 {
 	char *data;