The Driver does not set the +strict-align flag when targeting

[ARM] armv6m + netbsd. Tests are misssing for armv6m + darwin as well.

Differential Revision: http://reviews.llvm.org/D13217

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@249308 91177308-0d34-0410-b5e6-96231b3b80d8