AMDGPU: Remove -mcpu=SI

Leftover from before amdgcn/r600 split.

llvm-svn: 310277
diff --git a/llvm/test/CodeGen/AMDGPU/fminnum.f64.ll b/llvm/test/CodeGen/AMDGPU/fminnum.f64.ll
index 01b2674..475615e 100644
--- a/llvm/test/CodeGen/AMDGPU/fminnum.f64.ll
+++ b/llvm/test/CodeGen/AMDGPU/fminnum.f64.ll
@@ -1,4 +1,4 @@
-; RUN: llc -march=amdgcn -mcpu=SI < %s | FileCheck -check-prefix=SI -check-prefix=FUNC %s
+; RUN: llc -march=amdgcn -mcpu=tahiti < %s | FileCheck -check-prefix=SI -check-prefix=FUNC %s
 ; RUN: llc -march=amdgcn -mcpu=tonga < %s | FileCheck -check-prefix=SI -check-prefix=FUNC %s
 
 declare double @llvm.minnum.f64(double, double) #0