ARM: at91: AT91CAP9 has a macb device

commit

	ee621dd6 (net: atmel_macb Kconfig: remove long dependency line)

replaced a list of several explicit machines in the dependencies of MACB by
a single symbol that is selected by the respective machines. ee621dd6 missed
to let ARCH_AT91CAP9 select HAVE_NET_MACB though which is fixed here.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>