Fix eshell "ls" command for files larger than 1TiB

Fix eshell "ls" command for files larger than 1TiB

* lisp/eshell/esh-util.el (eshell-printable-size): Fix displaying file
sizes larger than 1 TiB or 1 TB.
* test/lisp/eshell/esh-util-tests.el
(esh-util-test/eshell-printable-size)
(esh-util-test/eshell-printable-size/zero)
(esh-util-test/eshell-printable-size/terabyte)
(esh-util-test/eshell-printable-size/use-colors)
(esh-util-test/eshell-printable-size/block-size)
(esh-util-test/eshell-printable-size/human-readable-arg): New tests.