[PPC64] Fix PR20071 (fctiduz generated for targets lacking that instruction)

PR20071 identifies a problem in PowerPC's fast-isel implementation for
floating-point conversion to integer.  The fctiduz instruction was added in
Power ISA 2.06 (i.e., Power7 and later).  However, this instruction is being
generated regardless of which 64-bit PowerPC target is selected.

The intent is for fast-isel to punt to DAG selection when this instruction is
not available.  This patch implements that change.  For testing purposes, the
existing fast-isel-conversion.ll test adds a RUN line for -mcpu=970 and tests
for the expected code generation.  Additionally, the existing test
fast-isel-conversion-p5.ll was found to be incorrectly expecting the
unavailable instruction to be generated.  I've removed these test variants
since we have adequate coverage in fast-isel-conversion.ll.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211627 91177308-0d34-0410-b5e6-96231b3b80d8
Fix up scoping in a few tests (and delete one that validates unnecessary behavior).

Most of this is just tests that were silently succeeding in spite of
schema changes I made over a year ago. Cleaning them up as they lead to
failures in a change I'm working on/will come soon.

test/DebugInfo/2010-01-19-DbgScope.ll was removed as it tested miscoping
where a DebugLoc described a location not in the current function. The
test case doesn't describe why this is a valid situation and should be
supported, so I'm removing it and shortly going to commit changes that
make this firmly unsupported/assert-fail.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211628 91177308-0d34-0410-b5e6-96231b3b80d8