support: Fix timespec printf

The patch print timespec members as intmax_t instead of long int.
It avoid the -Werror=format= build issue on x32:

  timespec.c: In function 'test_timespec_before_impl':
  timespec.c:32:23: error: format '%ld' expects argument of type 'long int',
  but argument 4 has type '__time_t' {aka 'const long long int'} [-Werror=format=]

Checked on x86_64-linux-gnu-x32, x86_64-linux-gnu, and i686-linux-gnu.

	* support/timespec.c (test_timespec_before_impl,
	test_timespec_equal_or_after_impl): print timespec member as intmax_t
	insted of long int.

Reviewed-by: Florian Weimer <fweimer@redhat.com>