Fix drm::control::Device::add_planar_buffer when GBM Bo uses DrmModif…

…ier::Invalid

When adding a GBM supplied buffer via add_planar_buffer, since commit
6cb3a27 the modifiers are fetched
directly from the planar buffer trait. What the code does not take into
account though is when the GBM bo returns DrmModifier::Invalid. In that
case add_fb2 expects 0 as modifier in the array for each plane,
instead of DRM_FORMAT_MOD_INVALID.

src/control/mod.rs

@@ -353,7 +353,9 @@ pub trait Device: super::Device {
     where
         B: buffer::PlanarBuffer + ?Sized,
     {
-        let modifier = planar_buffer.modifier();
+        let modifier = planar_buffer
+            .modifier()
+            .filter(|modifier| !matches!(modifier, DrmModifier::Invalid));
         let has_modifier = flags.contains(FbCmd2Flags::MODIFIERS);
         assert!((has_modifier && modifier.is_some()) || (!has_modifier && modifier.is_none()));
         let modifier = if let Some(modifier) = modifier {