gfs2: use lockref_init for gl_lockref

Move the initialization of gl_lockref from gfs2_init_glock_once() to
gfs2_glock_get().  This allows to use lockref_init() there.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Link: https://lore.kernel.org/r/20250130135624.1899988-2-agruenba@redhat.com


Signed-off-by: Christian Brauner <brauner@kernel.org>