powerpc/mpc5200: fix bestcomm Kconfig dependencies

Without this patch it is possible to select drivers which require
bestcomm support without bestcomm support being selected.  This
patch reworks the bestcomm dependencies to ensure the correct
bestcomm tasks are always enabled.

Reported-by: Hans Lehmann <hans.lehmann@ritter-elektronik.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 11f143f..231eeaf 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -1825,9 +1825,10 @@
 
 config FEC_MPC52xx
 	tristate "MPC52xx FEC driver"
-	depends on PPC_MPC52xx && PPC_BESTCOMM_FEC
+	depends on PPC_MPC52xx && PPC_BESTCOMM
 	select CRC32
 	select PHYLIB
+	select PPC_BESTCOMM_FEC
 	---help---
 	  This option enables support for the MPC5200's on-chip
 	  Fast Ethernet Controller