[PATCH 1/3] Fixes type of dyldInfo for glibc/bionic systems

Darwin and the BSDs define a tagged struct dl_info typedef'd as Dl_info. glibc
and bionic typedef an anonymous struct as Dl_info.

Fixes compiler complaint about:
src/Unwind/UnwindCursor.hpp:366:25: error: 'libunwind::AbstractUnwindCursor' has virtual functions but non-virtual destructor [-Werror,-Wnon-virtual-dtor]

LGTM

LGTM