fix compilation on musl

this should allow for compilation on musl libc

possibly fixes #150

Author: classabbyamp

src/decode_aprs.c

@@ -4113,11 +4113,7 @@ static void decode_tocall (decode_aprs_t *A, char *dest)
  * models before getting to the more generic APY.
  */
 
-#if defined(__WIN32__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__APPLE__)
 	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), tocall_cmp);
-#else
-	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), (__compar_fn_t)tocall_cmp);
-#endif
 	  }
 	  else {
 	    if ( ! A->g_quiet) {