drm/i915/gvt: remove module refcounting in intel_gvt_{,un}register_hypervisor

THIS_MODULE always is reference when a symbol called by it is used, so
don't bother with the additional reference.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-2-hch@lst.deReviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>

drivers/gpu/drm/i915/gvt/gvt.c

@@ -308,10 +308,6 @@ intel_gvt_register_hypervisor(const struct intel_gvt_mpt *m)
 	    m->type != INTEL_GVT_HYPERVISOR_XEN)
 		return -EINVAL;
 
-	/* Get a reference for device model module */
-	if (!try_module_get(THIS_MODULE))
-		return -ENODEV;
-
 	intel_gvt_host.mpt = m;
 	intel_gvt_host.hypervisor_type = m->type;
 	gvt = (void *)kdev_to_i915(intel_gvt_host.dev)->gvt;
@@ -321,7 +317,6 @@ intel_gvt_register_hypervisor(const struct intel_gvt_mpt *m)
 	if (ret < 0) {
 		gvt_err("Failed to init %s hypervisor module\n",
 			supported_hypervisors[intel_gvt_host.hypervisor_type]);
-		module_put(THIS_MODULE);
 		return -ENODEV;
 	}
 	gvt_dbg_core("Running with hypervisor %s in host mode\n",
@@ -335,6 +330,5 @@ intel_gvt_unregister_hypervisor(void)
 {
 	void *gvt = (void *)kdev_to_i915(intel_gvt_host.dev)->gvt;
 	intel_gvt_hypervisor_host_exit(intel_gvt_host.dev, gvt);
-	module_put(THIS_MODULE);
 }
 EXPORT_SYMBOL_GPL(intel_gvt_unregister_hypervisor);