Printf properly on systems without %zu [PR120086]

Printf properly on systems without %zu [PR120086]

Some systems don't support the %zu format modifier for size_t, such as
hppa64-hp-hpux. We don't really need the full width of size_t for
printing the number of prime paths as path counts of those sizes
would've already blown up the machine. For printing the vector size we
can use the formatting directives from hwint.h.

	PR gcov-profile/120086

gcc/ChangeLog:

	* gcov.cc (print_prime_path_lines): Use unsigned, format with
	%u.
	(print_prime_path_source): Likewise.
	(output_path_coverage): Format with HOST_SIZE_T_PRINT_UNSIGNED,
	use unsigned for pathno.