Fix Windows symupload after PE-only MD refactor.

- I think I previously fixed this for dump_syms, but must have missed
the symupload one because it didn't have a gn target.

Change-Id: Ibf4daa0dc874f329c2ee7c7b3d4de1ee6bc68d13
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/1682717
Reviewed-by: Mark Mentovai <mark@chromium.org>

src/tools/windows/symupload/symupload.cc

@@ -147,7 +147,7 @@ static bool DumpSymbolsToTempFile(const wchar_t *file,
     return false;
   }
 
-  bool success = writer.WriteMap(temp_file);
+  bool success = writer.WriteSymbols(temp_file);
   fclose(temp_file);
   if (!success) {
     _wunlink(temp_filename);