[llvm-objcopy] Changed command line parsing errors

Summary: Tidied up errors during command line parsing to be more consistent with the rest of llvm-objcopy errors.

Reviewers: jhenderson, rupprecht, espindola, alexshap

Reviewed By: jhenderson, rupprecht

Subscribers: emaste, arichardson, MaskRay, llvm-commits, jakehehrlich

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62973

llvm-svn: 363350
diff --git a/llvm/test/tools/llvm-objcopy/ELF/bad-output-format.test b/llvm/test/tools/llvm-objcopy/ELF/bad-output-format.test
index c24413a..932584c 100644
--- a/llvm/test/tools/llvm-objcopy/ELF/bad-output-format.test
+++ b/llvm/test/tools/llvm-objcopy/ELF/bad-output-format.test
@@ -15,5 +15,5 @@
   Type:            ET_EXEC
   Machine:         EM_386
 
-# BAD-OUTPUT-FORMAT: Invalid output format: 'xyz'
-# BAD-OUTPUT-FORMAT-BSD: Invalid output format: 'xyz-freebsd'
+# BAD-OUTPUT-FORMAT: invalid output format: 'xyz'
+# BAD-OUTPUT-FORMAT-BSD: invalid output format: 'xyz-freebsd'