peXXigen.c sanity checks

peXXigen.c sanity checks

Also fix a memory leak, and make some style changes.  I tend to read
(sizeof * x) as a multiplication of two variables, which I would not
do if binutils followed the gcc coding conventions consistently (see
https://gcc.gnu.org/codingconventions.html#Expressions).  (sizeof *x)
looks a lot better to me, or even (sizeof (*x)) which I've used here.

	* peXXigen.c (get_contents_sanity_check): New function.
	(pe_print_idata): Use it here..
	(pe_print_edata): ..and here.  Free data on error return.
	(rsrc_parse_entry): Check entry size read from file.
	(rsrc_parse_entries): Style fixes.
	(rsrc_process_section): Use bfd_malloc_and_get_section.
	(_bfd_XXi_final_link_postscript): Likewise.