iostat: Display device name at the end of line when option -h used

iostat: Display device name at the end of line when option -h used

iostat's option -h was intended to make the output more easily readable
by a human, especially when some devices had a long name that would make
the whole output shift around. In fact it added a '\n' to split the line
and the result was not particularly easier to read.
This patch moves the device name at the end of the line when option -h
is used without inserting more lines.
Option -h still sets option --human to automatically select the right
unit to display.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>