Fix missing output when using use_debug_fission

Bug: 1122182, 1144538
Change-Id: Ie7e293ba1eeeeeb41d694050c419878cf3420a0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2517700Reviewed-by: Peter Wen <wnwen@chromium.org>
Commit-Queue: Peter Wen <wnwen@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823632}

build/toolchain/gcc_solink_wrapper.py

@@ -139,6 +139,8 @@ def main():
   if link_only or collect_inputs_only:
     open(args.output, 'w').close()
     open(args.tocfile, 'w').close()
+    if args.dwp:
+      open(args.sofile + '.dwp', 'w').close()
 
   # Instead of linking, records all inputs to a file. This is used by
   # enable_resource_allowlist_generation in order to avoid needing to