[PATCH][gdb/ada] Fix -readnow FAILs

[Tom Tromey]

>>>>> "Tom" == Tom de Vries <tdevries@suse.de> writes:

Tom> 2020-03-24  Tom de Vries  <tdevries@suse.de>

Tom> 	PR ada/24671
Tom> 	* dwarf2/read.c (dw2_map_matching_symbols): Handle -readnow.

Thank you.  I think this is ok.

Now that we have lookup_name_info, I wonder if map_matching_symbols can
be removed entirely and replaced with expand_symtabs_matching.

Tom> +  if (dwarf2_per_objfile->index_table)

This should use "!= nullptr".

Tom