Change InfoZIP to not auto-append .zip to pathname

Author: jart

third_party/zip/README.cosmo

@@ -11,4 +11,5 @@ ORIGIN
 LOCAL CHANGES
 
   - Use Cosmopolitan's PCLMUL optimized CRC32
+  - Don't magically append .zip extension to filename argument
   - Improve find_next_signature() performance using unlocked stdio

third_party/zip/zipfile.c

@@ -413,6 +413,10 @@ char *ziptyp(s)
   if ((t = malloc(strlen(s) + 5)) == NULL)
     return NULL;
   strcpy(t, s);
+
+  // [jart] don't magically append .zip extension to filename argument
+  if (1) return t;
+
 #  ifdef __human68k__
   _toslash(t);
 #  endif