[llvm-objdump][test] Improve testing of some switches #3

This is the third commit in a series of patches to improve test coverage
of llvm-objdump. In this patch I have added a number of tests testing
various aspects of disassembly.

Reviewed by: MaskRay, grimar, rupprecht

Differential Revision: https://reviews.llvm.org/D62255

llvm-svn: 361489