powerpc/83xx: configure SIL SATA driver in 83xx-wide defconfig

to enable the storage controller on earlier rev. mpc834x itx boards.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/configs/mpc83xx_defconfig

@@ -712,7 +712,7 @@ CONFIG_ATA_SFF=y
 # CONFIG_SATA_QSTOR is not set
 # CONFIG_SATA_PROMISE is not set
 # CONFIG_SATA_SX4 is not set
-# CONFIG_SATA_SIL is not set
+CONFIG_SATA_SIL=y
 # CONFIG_SATA_SIS is not set
 # CONFIG_SATA_ULI is not set
 # CONFIG_SATA_VIA is not set