commit: factor out clear_commit_marks_for_object_array

commit: factor out clear_commit_marks_for_object_array

Factor out the code to clear the commit marks for a whole struct
object_array from builtin/checkout.c into its own exported function
clear_commit_marks_for_object_array and use it in bisect and bundle
as well.  It handles tags and commits and ignores objects of any
other type.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>