fs/notify: don't use module_init for non-modular inotify_user code

The INOTIFY_USER option is bool, and hence this code is either
present or absent.  It will never be modular, so using
module_init as an alias for __initcall is rather misleading.

Fix this up now, so that we can relocate module_init from
init.h into module.h in the future.  If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.

Note that direct use of __initcall is discouraged, vs. one
of the priority categorized subgroups.  As __initcall gets
mapped onto device_initcall, our use of fs_initcall (which
makes sense for fs code) will thus change this registration
from level 6-device to level 5-fs (i.e. slightly earlier).
However no observable impact of that small difference has
been observed during testing, or is expected.

Cc: John McCutchan <[email protected]>
Cc: Robert Love <[email protected]>
Cc: Eric Paris <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>

fs/notify/inotify/inotify_user.c

@@ -26,7 +26,7 @@
 #include <linux/fs.h> /* struct inode */
 #include <linux/fsnotify_backend.h>
 #include <linux/idr.h>
-#include <linux/init.h> /* module_init */
+#include <linux/init.h> /* fs_initcall */
 #include <linux/inotify.h>
 #include <linux/kernel.h> /* roundup() */
 #include <linux/namei.h> /* LOOKUP_FOLLOW */
@@ -812,4 +812,4 @@ static int __init inotify_user_setup(void)
 
 	return 0;
 }
-module_init(inotify_user_setup);
+fs_initcall(inotify_user_setup);