-use find_package_handle_standard_args() in FindOpenAL (#9496)

Alex

Modules/FindOpenAL.cmake

@@ -95,8 +95,9 @@ FIND_LIBRARY(OPENAL_LIBRARY
 )
 
 
-SET(OPENAL_FOUND "NO")
-IF(OPENAL_LIBRARY AND OPENAL_INCLUDE_DIR)
-  SET(OPENAL_FOUND "YES")
-ENDIF(OPENAL_LIBRARY AND OPENAL_INCLUDE_DIR)
+# handle the QUIETLY and REQUIRED arguments and set OPENAL_FOUND to TRUE if
+# all listed variables are TRUE
+INCLUDE(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(OpenAL  DEFAULT_MSG  OPENAL_LIBRARY OPENAL_INCLUDE_DIR)
 
+MARK_AS_ADVANCED(OPENAL_LIBRARY OPENAL_INCLUDE_DIR)