Enable UTF8 filename conversion for OS X

HFS drives are using combining characters, so use
UTF-8-MAC encoding for iconv

src/Makefile

@@ -155,6 +155,8 @@ else
 endif
     LOPT += -lz
 endif
+    COPT += -DENABLE_FILENAMES_ICONV
+    LOPT += -liconv
     # Use gcc for compiling. Use ncc to build a callgraph and analyze the code.
     CC = gcc
     #CC = nccgen -ncgcc -ncld -ncfabs

src/global.h

@@ -760,7 +760,11 @@ GFX2_GLOBAL int Line_number_in_INI_file;
 #include <iconv.h>
 
 #define TOCODE   "CP1252"
+#ifdef __macosx__
+#define FROMCODE "UTF-8-MAC"
+#else
 #define FROMCODE "UTF-8"
+#endif
 GFX2_GLOBAL iconv_t cd;
 GFX2_GLOBAL iconv_t cd_inv;
 #endif /* ENABLE_FILENAMES_ICONV */