Merge branch 'cp/apply-core-filemode'

Merge branch 'cp/apply-core-filemode'

"git apply" on a filesystem without filemode support have learned
to take a hint from what is in the index for the path, even when
not working with the "--index" or "--cached" option, when checking
the executable bit match what is required by the preimage in the
patch.

* cp/apply-core-filemode:
  apply: code simplification
  apply: correctly reverse patch's pre- and post-image mode bits
  apply: ignore working tree filemode when !core.filemode