fixup! Add -o - to test.

The update script doesn't require this to generate the test, but
running the test through lit does.

Author: topperc

llvm/test/CodeGen/RISCV/GlobalISel/knownbits-copy-crash.mir

@@ -1,5 +1,5 @@
 # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
-# RUN: llc %s -mtriple=riscv64 -mattr=+zbb,+f -run-pass=instruction-select | FileCheck %s
+# RUN: llc -mtriple=riscv64 -mattr=+zbb,+f -run-pass=instruction-select %s -o - | FileCheck %s
 
 ---
 name:            foo