Error when 32-bit ar tries to handle 4G or larger files

Error when 32-bit ar tries to handle 4G or larger files

We used to silently truncate the size returned by stat() to 32 bits.
While it is possible to make binutils handle a 64-bit off_t on a
32-bit host, to me the effort needed doesn't seem worth the benefit.
Instead, error if we truncate the size.  I've written the test the way
I have to avoid a signed/unsigned warning.

	PR 22116
	* archive.c (bfd_ar_hdr_from_filesystem): Detect when status.st_size
	overflows bfd_size_type.