v3d/drm-shim: add support for multisync

This is needed for Vulkan and makes vulkaninfo succeed using drm-shim.

Signed-off-by: Job Noorman <jnoorman@igalia.com>
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36509>

src/broadcom/drm-shim/v3d_noop.c

@@ -131,6 +131,9 @@ v3d_ioctl_get_param(int fd, unsigned long request, void *arg)
         case DRM_V3D_PARAM_SUPPORTS_PERFMON:
                 gp->value = 1;
                 return 0;
+        case DRM_V3D_PARAM_SUPPORTS_MULTISYNC_EXT:
+                gp->value = 1;
+                return 0;
         default:
                 break;
         }