monitor mode: deconflict with private global mangling
The synthesized probe body for monitor mode control needs to refer to
globals that may be declared private inside a tapset, in order to
clear them. It needs to pierce the mangling-based name-hiding, so
that when the synthetic fragment is symbol-resolved, it will find the
mangled private globals to manipulate. This is implemented by an
optional mode-flag in the symresolution_info class to suppress
global-mangling.