apply.c: fix whitespace-only mismerge

apply.c: fix whitespace-only mismerge

4af9a7d3 ("Merge branch 'bc/object-id'", 2016-09-19) involved
merging a lot of changes made to builtin/apply.c on the side branch
manually to apply.c as an intervening commit 13b5af22 ("apply: move
libified code from builtin/apply.c to apply.{c,h}", 2016-04-22)
moved a lot of the lines changed on the side branch to a different
file apply.c at the top-level, requiring manual patching of it.
Apparently, the maintainer screwed up and made the code indent in a
funny way while doing so.

Reported-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>