rust: drm/kms: Add RawCrtcState::active()

A binding for checking drm_crtc_state.active.

Signed-off-by: Lyude Paul <lyude@redhat.com>

rust/kernel/drm/kms/crtc.rs

@@ -496,6 +496,14 @@ pub trait RawCrtcState: AsRawCrtcState {
         //   state
         unsafe { <Self::Crtc as AsRawCrtc>::from_raw((*self.as_raw()).crtc) }
     }
+
+    /// Returns whether or not the CRTC is active in this atomic state.
+    fn active(&self) -> bool {
+        // SAFETY: `active` and the rest of its containing bitfield can only be modified from the
+        // atomic check context, and are invariant beyond that point - so our interface can ensure
+        // this access is serialized
+        unsafe { (*self.as_raw()).active }
+    }
 }
 impl<T: AsRawCrtcState> RawCrtcState for T {}