decoder/flac: move FlacIOHandle.?xx to lib/xiph/

Makefile.am

@@ -1199,8 +1199,8 @@ endif
 if ENABLE_FLAC
 libdecoder_a_SOURCES += \
 	src/lib/xiph/FlacMetadataIterator.hxx \
+	src/lib/xiph/FlacIOHandle.cxx src/lib/xiph/FlacIOHandle.hxx \
 	src/decoder/plugins/FlacInput.cxx src/decoder/plugins/FlacInput.hxx \
-	src/decoder/plugins/FlacIOHandle.cxx src/decoder/plugins/FlacIOHandle.hxx \
 	src/decoder/plugins/FlacMetadata.cxx src/decoder/plugins/FlacMetadata.hxx \
 	src/decoder/plugins/FlacPcm.cxx src/decoder/plugins/FlacPcm.hxx \
 	src/decoder/plugins/FlacDomain.cxx src/decoder/plugins/FlacDomain.hxx \

src/decoder/plugins/FlacMetadata.hxx

@@ -21,7 +21,7 @@
 #define MPD_FLAC_METADATA_H
 
 #include "Compiler.h"
-#include "FlacIOHandle.hxx"
+#include "lib/xiph/FlacIOHandle.hxx"
 
 #include <FLAC/metadata.h>