Fixed bot failure after 4042ada

Added '-' in `mtriple` in test case
There was a bot failure due to this:
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-debian/builds/6790

Author: SouraVX

llvm/test/DebugInfo/dwarfdump-dataLocationExp.ll

@@ -1,7 +1,7 @@
 ;; This test checks whether DW_AT_data_location attribute
 ;; accepts DIExpression.
 
-; RUN: llc mtriple=x86_64-unknown-linux-gnu %s -filetype=obj -o %t.o
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu %s -filetype=obj -o %t.o
 ; RUN: llvm-dwarfdump  %t.o | FileCheck %s
 
 ;; Test whether DW_AT_data_location is generated.