ata: Migrate CONFIG_FSL_SATA to Kconfig

Use 'imply' here liberally to avoid the combinatorial explosion of
defconfig changes in the PowerPC boards.

Signed-off-by: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
diff --git a/configs/MPC8315ERDB_defconfig b/configs/MPC8315ERDB_defconfig
index fc846b2..473b9a6 100644
--- a/configs/MPC8315ERDB_defconfig
+++ b/configs/MPC8315ERDB_defconfig
@@ -19,6 +19,7 @@
 CONFIG_CMD_MTDPARTS=y
 CONFIG_MTDIDS_DEFAULT="nand0=e0600000.flash"
 CONFIG_MTDPARTS_DEFAULT="mtdparts=e0600000.flash:512k(uboot),128k(env),6m@1m(kernel),-(fs)"
+CONFIG_FSL_SATA=y
 # CONFIG_MMC is not set
 CONFIG_MTD_NOR_FLASH=y
 CONFIG_PHYLIB=y