hwclock: remove custom errno string

hwclock: remove custom errno string

Custom errno messages are unnecessary and problematic for translators.

hwclock --directisa
hwclock: iopl() port access failed: Operation not permitted
hwclock: root privileges may be required

The custom errno message is misleading. We do not know what
the system permissions are set to. The default errno string is
correct, and enough.

Patched:
hwclock --directisa
hwclock: iopl() port access failed: Operation not permitted

root@:~# hwclock --directisa -D
Using direct ISA access to the clock
2017-07-24 14:49:17.782716-0400

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