[llvm-objcopy] Add test to check that architecture specific values are not...

[llvm-objcopy] Add test to check that architecture specific values are not used on wrong architecture.

This change adds a test that checks the an error is produced when a hexagon
specific reserved section index is used but e_machine is not EM_HEXAGON.

Differential Revision: https://reviews.llvm.org/D38017

llvm-svn: 313661