[5/5 PATCH/RFC PPC64] tests for power8 keyword

Assorted tests for the power8/pwr8 keyword.

diff --git a/tools/clang/test/Driver/clang-translation.c b/tools/clang/test/Driver/clang-translation.c
index 54e5bbe..a525b7f 100644
--- a/tools/clang/test/Driver/clang-translation.c
+++ b/tools/clang/test/Driver/clang-translation.c
@@ -71,6 +71,12 @@
// PPCPWR7: "-target-cpu" "pwr7"

// RUN: %clang -target powerpc64-unknown-linux-gnu \
+// RUN: -### -S %s -mcpu=power8 2>&1 | FileCheck -check-prefix=PPCPWR8 %s
+// PPCPWR8: clang
+// PPCPWR8: "-cc1"
+// PPCPWR8: "-target-cpu" "pwr8"