drivers/net: Kconfig & Makefile cleanup

The is does a general cleanup of the drivers/net/ Kconfig and
Makefile.  This patch create a "core" option and places all
the networking core drivers into this option (default is yes
for this option).  In addition, it alphabitizes the Kconfig
driver options.

As a side cleanup, found that the arcnet, token ring, and PHY
Kconfig options were a tri-state option and should have been
a bool option.

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/tokenring/Kconfig b/drivers/net/tokenring/Kconfig
index 0f70158..c7e0149 100644
--- a/drivers/net/tokenring/Kconfig
+++ b/drivers/net/tokenring/Kconfig
@@ -4,7 +4,7 @@
 
 # So far, we only have PCI, ISA, and MCA token ring devices
 menuconfig TR
-	tristate "Token Ring driver support"
+	bool "Token Ring driver support"
 	depends on NETDEVICES && !UML
 	depends on (PCI || ISA || MCA || CCW || PCMCIA)
 	select LLC