Remove all the vio device driver code from hvc_console.c

This will allow us to separate hvsi, hvc, and allow hvc_console to be used
without the ppc64 vio layer.
Signed-off-by: NMilton Miller <miltonm@bga.com>
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>