dr_flac: Ensure NEON codepath is taken for Windows ARM64

Patch based on mackron/dr_libs@5c6b5b1638c625d82ac350ce4c1e7581cc10f292

src/libraries/dr/dr_flac.h

@@ -1020,7 +1020,7 @@ drflac_bool32 drflac_next_cuesheet_track(drflac_cuesheet_track_iterator* pIter,
     #define DRFLAC_X64
 #elif defined(__i386) || defined(_M_IX86)
     #define DRFLAC_X86
-#elif defined(__arm__) || defined(_M_ARM)
+#elif defined(__arm__) || defined(_M_ARM) || defined(_M_ARM64)
     #define DRFLAC_ARM
 #endif