drm/amd/display: dc_get_vmid_use_vector() crashes when get called

[Why]
int i can go out of boundary which will cause crash

[How]
Fixed the maximum value of i to avoid i going out of boundary
Signed-off-by: Peikang Zhang <peikang.zhang@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_vm_helper.c

@@ -62,7 +62,7 @@ int dc_get_vmid_use_vector(struct dc *dc)
 	int i;
 	int in_use = 0;
 
-	for (i = 0; i < dc->vm_helper->num_vmid; i++)
+	for (i = 0; i < MAX_HUBP; i++)
 		in_use |= dc->vm_helper->hubp_vmid_usage[i].vmid_usage[0]
 			| dc->vm_helper->hubp_vmid_usage[i].vmid_usage[1];
 	return in_use;