* vax-tdep.h (vax_regnum): Add VAX_R0_REGNUM and VAX_R1_REGNUM.

* vax-tdep.h (vax_regnum): Add VAX_R0_REGNUM and VAX_R1_REGNUM.
* vax-tdep.c (vax_store_arguments): Remove struct_return and
struct_addr arguments.  Don't push return value address.
(vax_push_dummy_call): Don't pass STRUCT_RETURN and STRUCT_ADDR as
arguments to vax_store_arguments.  Store return value address in
R1.
(vax_store_struct_return, vax_extract_return_value)
(vax_store_return_value): Remove functions.
(vax_return_value): New function.
(vax_gdbarch_init): Set return value.  Don't set
deprecated_store_struct_return, deprecated_extract_struct_return
and deprecated_store_return_value.