Stricter prototyping, to force type conversions between 64-bit target and

Stricter prototyping, to force type conversions between 64-bit target and
32-bit host values.

* libbfd.c (bfd_xmalloc_by_size_t): New function.
* opncls.c (bfd_cache_init, bfd_open_file): Add prototypes to declarations.
(obstack_chunk_alloc): Use bfd_xmalloc_by_size_t.
(new_bfd): Prototype-style definition, using DEFUN.
(bfd_alloc_grow, bfd_alloc, bfd_zalloc, bfd_realloc): Size argument is type
size_t, not bfd_size_type.
* ieee.c (obstack_chunk_alloc): Use bfd_xmalloc_by_size_t.
* bfd.c (bfd_default_error_trap, bfd_error_trap,
bfd_error_nonrepresentabltrap): Prototypes.
* libbfd-in.h (bfd_alloc, bfd_zalloc, bfd_realloc, bfd_alloc_grow): Adjusted
prototypes for arg type change.
* archive.c (get_elt_at_filepos, do_slurp_bsd_armap, normalize,
do_slurp_coff_armap, bfd_construct_extended_name_table): Prototypes.