drm/arm/malidp: Silence informational message

When checking for unsupported expect an error is printed every time.
This spams the log for platforms where this is expected, e.g. ls1028a
having a Vivante (etnaviv) GPU and Mali display processor.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://lore.kernel.org/r/20250523064042.3275926-1-alexander.stein@ew.tq-group.com

Author: tq-steina

drivers/gpu/drm/arm/malidp_planes.c

@@ -159,7 +159,7 @@ bool malidp_format_mod_supported(struct drm_device *drm,
 	}
 
 	if (!fourcc_mod_is_vendor(modifier, ARM)) {
-		DRM_ERROR("Unknown modifier (not Arm)\n");
+		DRM_DEBUG_KMS("Unknown modifier (not Arm)\n");
 		return false;
 	}