Fixing problems in lli's RemoteMemoryManager.

This fixes a problem from a previous check-in where a return value was omitted.

Previously the remote/stubs-remote.ll and remote/stubs-sm-pic.ll tests were reporting passes, but they should have been failing.  Those tests attempt to link against an external symbol and remote symbol resolution is not supported.  The old RemoteMemoryManager implementation resulted in local symbols being used for resolution and the child process crashed but the test didn't notice.  With this check-in remote symbol resolution fails, and so the test (correctly) fails.