MPC5121e ADS PCI support take 3

Adds PCI support for MPC5121

Tested with drivers/net/rtl8139.c

Support is conditional since PCI on old silicon does not work.

ads5121_PCI_config turns on PCI

In this version, condition compilation of PCI code has been moved
from ifdef in board/ads5121/pci.c to board/ads5121/Makefile as
suggested by Jean-Christophe PLAGNIOL-VILLARD

Signed-off-by: John Rigby <jrigby@freescale.com>
diff --git a/board/ads5121/ads5121.c b/board/ads5121/ads5121.c
index 462f41d..8629b03 100644
--- a/board/ads5121/ads5121.c
+++ b/board/ads5121/ads5121.c
@@ -34,6 +34,7 @@
 			 CLOCK_SCCR1_PSCFIFO_EN |			\
 			 CLOCK_SCCR1_DDR_EN |				\
 			 CLOCK_SCCR1_FEC_EN |				\
+			 CLOCK_SCCR1_PCI_EN |				\
 			 CLOCK_SCCR1_TPR_EN)
 
 #define SCCR2_CLOCKS_EN	(CLOCK_SCCR2_MEM_EN |		\