Test load unloading of modules with libraries-svr4

Summary:
This doubles the 3 tests running right now on linux by also executing each test with libraries-svr4 enabled.
Not sure if there's a better way to do this as I had to copy/paste all the decorators as well...

Reviewers: labath, clayborg, xiaobai

Reviewed By: labath

Subscribers: srhines, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D65129

llvm-svn: 367247