Added -p / --no-params flag to skip demangling function parameters
similar to how it is supported by GNU c++filt tool.
There are cases when users want to demangle a large number of symbols in
bulk, for example, at startup, and do not care about function parameters
and overloads at that time. Skipping the demangling of parameter types
led to a measurable improvement in performance. Our users reported about
15% speed up with GNU c++filt and we expect similar results with
llvm-cxxfilt with this patch.
569ec185f5
