lddigest 32-bit support and gcc-4 compile errors

lddigest 32-bit support and gcc-4 compile errors

	* ld.texi: Revert 2023-03-08 commit 9a534b9f8e3d.
	* testsuite/ld-scripts/crc64-poly.d: Likewise.
	* testsuite/ld-scripts/crc64-poly.t: Likewise.
	* lddigest.c: Formatting.
	(get_uint64_t): New function.
	(lang_add_digest): Take etree_type* args.  Replace "illegal" with
	"invalid" in error message.
	* lddigest.h (lang_add_digest): Update prototype.
	* lddigest_tab.c (algorithms): Work around gcc-4 errors.
	* ldgram.y (polynome): Adjust lang_add_digest call.
	* testsuite/ld-scripts/crc64-poly-size.d: Update expected error.