decoder/wildmidi: use NarrowPath, fixing the Windows build

NEWS

@@ -5,6 +5,7 @@ ver 0.21.24 (not yet released)
   - simple: fix crash when mounting twice
 * decoder
   - wildmidi: attempt to detect WildMidi using pkg-config
+  - wildmidi: fix Windows build failure
 * Android
   - fix build failure with Android NDK r21
 * Windows

src/decoder/plugins/WildmidiDecoderPlugin.cxx

@@ -25,6 +25,7 @@
 #include "fs/AllocatedPath.hxx"
 #include "fs/FileSystem.hxx"
 #include "fs/Path.hxx"
+#include "fs/NarrowPath.hxx"
 #include "Log.hxx"
 #include "PluginUnavailable.hxx"
 
@@ -53,7 +54,8 @@ wildmidi_init(const ConfigBlock &block)
 	AtScopeExit() { WildMidi_ClearError(); };
 #endif
 
-	if (WildMidi_Init(path.c_str(), wildmidi_audio_format.sample_rate,
+	if (WildMidi_Init(NarrowPath(path),
+			  wildmidi_audio_format.sample_rate,
 			  0) != 0) {
 #ifdef LIBWILDMIDI_VERSION
 		/* WildMidi_GetError() requires libwildmidi 0.4 */
@@ -96,7 +98,7 @@ wildmidi_file_decode(DecoderClient &client, Path path_fs)
 	midi *wm;
 	const struct _WM_Info *info;
 
-	wm = WildMidi_Open(path_fs.c_str());
+	wm = WildMidi_Open(NarrowPath(path_fs));
 	if (wm == nullptr)
 		return;
 
@@ -136,7 +138,7 @@ wildmidi_file_decode(DecoderClient &client, Path path_fs)
 static bool
 wildmidi_scan_file(Path path_fs, TagHandler &handler) noexcept
 {
-	midi *wm = WildMidi_Open(path_fs.c_str());
+	midi *wm = WildMidi_Open(NarrowPath(path_fs));
 	if (wm == nullptr)
 		return false;