* symtab.cc (Symbol_table::define_default_version): New function,
broken out of add_from_object.
(Symbol_table::add_from_object): Call define_default_version.
(Symbol_table::define_special_symbol): Add resolve_oldsym
parameter. Change all callers. If the version for a symbol comes
from a version script, resolve it with the symbol with the same
name with no version. Also add the symbol without a version if
appropriate.
(do_define_in_output_data): If resolving with oldsym, don't delete
sym.
(do_define_in_output_segment): Likewise.
(do_define_as_constant): Likewise.
* symtab.h (class Symbol_table): Update declarations.