Enable TestCallThatRestarts test on Linux.

This is related to:
http://llvm.org/bugs/show_bug.cgi?id=15278

I ran this 20 times in a row without failure at svn r202440 on Ubuntu
12.04 LTS x86_64 using July 2013 libedit and gcc 4.8.2.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@202448 91177308-0d34-0410-b5e6-96231b3b80d8