vfs: reorder checks in may_create_in_sticky

vfs: reorder checks in may_create_in_sticky

The routine is called for all directories on file creation and weirdly
postpones the check if the dir is sticky to begin with. Instead it first
checks fifos and regular files (in that order), while avoidably pulling
globals.

No functional changes.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20240620120359.151258-1-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>