[NVPTX] Fix ptxas-verify line.

Without specifying -arch=sm_90, we get this error:
ptxas fatal   : SM version specified by .target is higher than default SM version assumed

Author: akuegel

llvm/test/CodeGen/NVPTX/combine-min-max.ll

@@ -1,7 +1,7 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc < %s -mcpu=sm_90 -mattr=+ptx80 -O3 | FileCheck %s --check-prefixes=CHECK,SM90
 ; RUN: llc < %s -mcpu=sm_20 -O3 | FileCheck %s --check-prefixes=CHECK,SM20
-; RUN: %if ptxas-12.0 %{ llc < %s -mcpu=sm_90 -mattr=+ptx80 -O3 | %ptxas-verify %}
+; RUN: %if ptxas-12.0 %{ llc < %s -mcpu=sm_90 -mattr=+ptx80 -O3 | %ptxas-verify -arch=sm_90 %}
 ; RUN: %if ptxas-12.0 %{ llc < %s -mcpu=sm_20 -O3 | %ptxas-verify %}
 
 target triple = "nvptx64-nvidia-cuda"