[ARM] Fix Thumb(-2) diagnostic tests.

Changing the diagnostic message for out of range branch targets in 191686 broke the tests.

The diagnostic message for out of range branch targets was changed to be more consistent with the other diagnostics.
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191691 91177308-0d34-0410-b5e6-96231b3b80d8