[lldb] [gdb-remote server] Abstract away getting current process

Introduce new m_current_process and m_continue_process variables that
keep the pointers to currently selected process.  At this moment, this
is equivalent to m_debugged_process_up but it lays foundations for
the future multiprocess support.

Differential Revision: https://reviews.llvm.org/D100256

GitOrigin-RevId: f1812a284f28e5b142e63d5deeb340be3ca5d4b3
2 files changed