[PowerPC] Fix CodeGen/PowerPC/crbit-asm.ll test for -O1

Add the crbits processor feature so that the test can be run at -O1, etc.
regardless of the default crbits setting.

Fixes PR23778.

llvm-svn: 251548
diff --git a/llvm/test/CodeGen/PowerPC/crbit-asm.ll b/llvm/test/CodeGen/PowerPC/crbit-asm.ll
index 36de343..41e65af 100644
--- a/llvm/test/CodeGen/PowerPC/crbit-asm.ll
+++ b/llvm/test/CodeGen/PowerPC/crbit-asm.ll
@@ -1,4 +1,5 @@
 ; RUN: llc -mcpu=pwr7 < %s | FileCheck %s
+; RUN: llc -O1 -mcpu=pwr7 < %s | FileCheck %s
 target datalayout = "E-m:e-i64:64-n32:64"
 target triple = "powerpc64-unknown-linux-gnu"
 
@@ -55,5 +56,5 @@
 ; CHECK: blr
 }
 
-attributes #0 = { nounwind }
+attributes #0 = { nounwind "target-features"="+crbits" }