x86: Switch all boards to use DM SCSI

After MMC is converted to DM, convert to use DM SCSI as well for all
x86 boards and imply BLK for both MMC and SCSI drivers.

CONFIG_SCSI_DEV_LIST is no longer used. Clean them up.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/broadwell/Kconfig b/arch/x86/cpu/broadwell/Kconfig
index 7e71325..b421f18 100644
--- a/arch/x86/cpu/broadwell/Kconfig
+++ b/arch/x86/cpu/broadwell/Kconfig
@@ -10,6 +10,7 @@
 	imply HAVE_INTEL_ME
 	imply ENABLE_MRC_CACHE
 	imply ENV_IS_IN_SPI_FLASH
+	imply AHCI_PCI
 	imply ICH_SPI
 	imply INTEL_BROADWELL_GPIO
 	imply SCSI