parisc: Update defconfigs which were missing CONFIG_NET.

Commit df568d8e ("scsi: Use 'depends' with LIBFC instead of
'select'.")  removed what happened to be the only instance of 'select
NET'. Defconfigs that were relying on the select now lack networking
support.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/parisc/configs/a500_defconfig

@@ -31,6 +31,7 @@ CONFIG_PD6729=m
 CONFIG_I82092=m
 # CONFIG_SUPERIO is not set
 # CONFIG_CHASSIS_LCD_LED is not set
+CONFIG_NET=y
 CONFIG_PACKET=y
 CONFIG_UNIX=y
 CONFIG_XFRM_USER=m