[driver] When generating temporary files allow a prefix to be added.  In many
cases we want the prefix to be the original file name less the suffix.  For an
input such as test.c to named temporary would be something like test-3O4Clq.o
Part of <rdar://problem/8314451>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138662 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed