Rewrite three tests that had truly egregious abuses of 'grep' in them to

Rewrite three tests that had truly egregious abuses of 'grep' in them to
use FileCheck.

Aside from removing a dependence on TCL-style quoting, this also makes
the tests ... significantly more robust. =] It would be really, *really*
great of the maintainer(s) of the CellSPU backend went through and
systematically rewrite these tests to use FileCheck. There are a lot
more that have nearly this bad of abuses.

Another step along the path to a TclTest-free testsuite.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159523 91177308-0d34-0410-b5e6-96231b3b80d8