[AArch64] Enable PostRAScheduler for AArch64 generic build.

Disable post-ra scheduler for perturbed tests to appease the bots and to
preserve the history of the tests.

http://reviews.llvm.org/D15652

llvm-svn: 256158
diff --git a/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll b/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
index fbe5e8e..1820b81 100644
--- a/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
+++ b/llvm/test/CodeGen/AArch64/aarch64-dynamic-stack-layout.ll
@@ -1,4 +1,4 @@
-; RUN: llc -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mtriple=aarch64-none-linux-gnu -disable-post-ra < %s | FileCheck %s
 
 ; This test aims to check basic correctness of frame layout &
 ; frame access code. There are 8 functions in this test file,