[llvm-strip] Add support for -p/--preserve-dates

Summary: [llvm-strip] Preserve access/modification timestamps when -p is used.

Reviewers: jakehehrlich, jhenderson, alexshap

Reviewed By: jhenderson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50744

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@339921 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed