hwclock: make epoch functions alpha only

hwclock: make epoch functions alpha only

It's been 19.1315 years since the comment below was written and the kernel
has actually gone further away from allowing an RTC epoch on ISA machines.

/*
 * Maintenance note: This should work on non-Alpha machines, but the
 * evidence today (98.03.04) indicates that the kernel only keeps the epoch
 * value on Alphas. If that is ever fixed, this function should be changed.
 */

The current behavior is to accept the epoch options on ISA machines
only to print a lengthy message explaining that you cannot use them.

This patch removes that behavior, making the epoch functions truly Alpha
only, as the man-page states that they are.

* sys-utils/hwclock.c: make epoch function alpha only.
* sys-utils/hwclock.h: same.

Signed-off-by: J William Piggott <elseifthen@gmx.com>