Corrected undefined CMAKE_BUILD_TYPE handling

CMakeConf.cmake

@@ -72,7 +72,8 @@ if(NOT DEFINED GOLD_SUFFIX)
 endif()
 
 function(TARGET_GOLD_SOURCES TARGET PREFIX)
-	if(${CMAKE_BUILD_TYPE} MATCHES "Debug")
+	#message("CMAKE_BUILD_TYPE=\"${CMAKE_BUILD_TYPE}\"")
+	if(CMAKE_BUILD_TYPE MATCHES "^(Debug|)$")
 		message("Using gold check file ${PREFIX}debug.cpp")
 		target_sources(${TARGET} PUBLIC "${PREFIX}debug.cpp")
 	else()