More fixes for invalid memory accesses, uncovered by valgrind and binary fuzzers.
PR binutils/17512
* coffcode.h (coff_slurp_line_table): Initialise the parts of the
line number cache that would not be initialised by the copy from
the new line number table.
(coff_classify_symbol): Allow for _bfd_coff_internal_syment_name
returning NULL.
* coffgen.c (coff_get_normalized_symbols): Get the external
symbols before allocating space for the internal symbols, in case
the get fails.
* elf.c (_bfd_elf_slurp_version_tables): Only allocate a verref
array if one is needed. Likewise with the verdef array.
* peXXigen.c (_bfd_XXi_swap_sym_in): Replace abort()'s with error
messages.
(_bfd_XXi_swap_aux_in): Make sure that all fields of the aux
structure are initialised.
(pe_print_edata): Avoid reading off the end of the data buffer.