Convert CONFIG_SCSI to Kconfig

This converts the following to Kconfig:
   CONFIG_SCSI

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/powerpc/cpu/mpc85xx/Kconfig b/arch/powerpc/cpu/mpc85xx/Kconfig
index 4db687c..a4b2761 100644
--- a/arch/powerpc/cpu/mpc85xx/Kconfig
+++ b/arch/powerpc/cpu/mpc85xx/Kconfig
@@ -117,6 +117,7 @@
 	select ARCH_MPC8572
 # Use DDR3 controller with DDR2 DIMMs on this board
 	select SYS_FSL_DDRC_GEN3
+	imply SCSI
 
 config TARGET_P1010RDB_PA
 	bool "Support P1010RDB_PA"
diff --git a/arch/powerpc/cpu/mpc86xx/Kconfig b/arch/powerpc/cpu/mpc86xx/Kconfig
index fcac658..2cc180d 100644
--- a/arch/powerpc/cpu/mpc86xx/Kconfig
+++ b/arch/powerpc/cpu/mpc86xx/Kconfig
@@ -21,6 +21,7 @@
 config TARGET_MPC8641HPCN
 	bool "Support MPC8641HPCN"
 	select ARCH_MPC8641
+	imply SCSI
 
 config TARGET_XPEDITE517X
 	bool "Support xpedite517x"