Update gdbserver_tests filter for newer GDB version.

Update gdbserver_tests filter for newer GDB version.

- Newer gdb say Thread .... hit Breakpoint, we expect just Breakpoint.
- We expect "Program received" instead of "Thread .... received"
- Ordering of '  Thread .... (tid .' might differ between gdb version,
  so remove all such lines except the "current" one (starts with '*').

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15844