[Bugpoint] fix another use-after-move. NFC

Summary:
This was flagged in https://www.viva64.com/en/b/0629/ under "Snippet No.
7".

These statements are order independent, short of the use-after-move.

Reviewers: echristo, srhines, RKSimon

Reviewed By: RKSimon

Subscribers: dblaikie, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62114

llvm-svn: 362267