drm_hwcomposer: Use pragma once instead of include guards

Some of existing include guards were copy-pasted without modification,
therefore have incorrect name. Switch to 'pragma once' in order to fix
it and avoid such copy-paste issues in the future.

Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
diff --git a/bufferinfo/legacy/BufferInfoMaliHisi.h b/bufferinfo/legacy/BufferInfoMaliHisi.h
index cc37491..35c7989 100644
--- a/bufferinfo/legacy/BufferInfoMaliHisi.h
+++ b/bufferinfo/legacy/BufferInfoMaliHisi.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef BUFFERINFOMALIHISI_H_
-#define BUFFERINFOMALIHISI_H_
+#pragma once
 
 #include <hardware/gralloc.h>
 
@@ -33,5 +32,3 @@
   uint64_t ConvertGrallocFormatToDrmModifiers(uint64_t flags, bool is_rgb);
 };
 }  // namespace android
-
-#endif