AMDGPU: Remove -mcpu=SI

Leftover from before amdgcn/r600 split.

llvm-svn: 310277
diff --git a/llvm/test/CodeGen/AMDGPU/lds-zero-initializer.ll b/llvm/test/CodeGen/AMDGPU/lds-zero-initializer.ll
index 53c1c72..a3b3d7b 100644
--- a/llvm/test/CodeGen/AMDGPU/lds-zero-initializer.ll
+++ b/llvm/test/CodeGen/AMDGPU/lds-zero-initializer.ll
@@ -1,4 +1,4 @@
-; RUN: not llc -march=amdgcn -mcpu=SI < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=amdgcn -mcpu=tahiti < %s 2>&1 | FileCheck %s
 ; RUN: not llc -march=amdgcn -mcpu=tonga < %s 2>&1 | FileCheck %s
 
 ; CHECK: in function load_zeroinit_lds_global{{.*}}: unsupported initializer for address space