* ldd.cc (longopts): Add --dll option.

* ldd.cc (longopts): Add --dll option.
(get_module_filename): Generalized wrapper function which avoid path length
restrictions.
(load_dll): Handle special-case of inspecting a DLL.
(start_process): Accept an output parameter "isdll".  Detect when file to start
is a DLL and start a wrapper instead.
(print_dlls_and_kill_inferior): When dealing with a DLL, avoid printing
everything before the DLL itself first appears.  (This is not strictly correct
and should be fixed eventually)
(report): Deal with DLLs.  Don't set a breakpoint for DLLs, just let captive
ldd process terminate normally.  Pass dll info to print_dlls_and_kill_inferior.
(main): Handle special-case "--dll" option by loading the DLL and exiting.