Set some tests to an unknown vendor and OS

This avoids llc using the hosts OS/vendor as defaults and triggering
unwanted behaviour in the tests. This should deal with the buildbot
breakages on windows after r283140.

llvm-svn: 283149
diff --git a/llvm/test/CodeGen/Mips/tls.ll b/llvm/test/CodeGen/Mips/tls.ll
index 8968567..b416f1f 100644
--- a/llvm/test/CodeGen/Mips/tls.ll
+++ b/llvm/test/CodeGen/Mips/tls.ll
@@ -1,8 +1,8 @@
-; RUN: llc -march=mipsel -disable-mips-delay-filler -relocation-model=pic < %s | \
+; RUN: llc -mtriple=mipsel-- -disable-mips-delay-filler -relocation-model=pic < %s | \
 ; RUN:     FileCheck %s -check-prefixes=PIC,CHECK
-; RUN: llc -march=mipsel -relocation-model=static -disable-mips-delay-filler < \
+; RUN: llc -mtriple=mipsel-- -relocation-model=static -disable-mips-delay-filler < \
 ; RUN:     %s | FileCheck %s -check-prefixes=STATIC,CHECK
-; RUN: llc -march=mipsel -relocation-model=static -disable-mips-delay-filler \
+; RUN: llc -mtriple=mipsel-- -relocation-model=static -disable-mips-delay-filler \
 ; RUN:     -mips-fix-global-base-reg=false < %s  | \
 ; RUN:     FileCheck %s -check-prefixes=STATICGP,CHECK