smc911x: SuperH architecture support

Enable the smc911x driver for the SuperH architecture.  While at it remove
the unused SMC_USE_SH_DMA definition.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>