Convert CONFIG_ENV_IS_IN_SPI_FLASH to Kconfig

This converts the following to Kconfig:
   CONFIG_ENV_IS_IN_SPI_FLASH

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/db-88f6820-gp_defconfig b/configs/db-88f6820-gp_defconfig
index f0b0d69..6c6083d 100644
--- a/configs/db-88f6820-gp_defconfig
+++ b/configs/db-88f6820-gp_defconfig
@@ -9,6 +9,7 @@
 CONFIG_SPL_SPI_SUPPORT=y
 CONFIG_DEFAULT_DEVICE_TREE="armada-388-gp"
 CONFIG_DEBUG_UART=y
+CONFIG_ENV_IS_IN_SPI_FLASH=y
 CONFIG_BOOTDELAY=3
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 # CONFIG_DISPLAY_BOARDINFO is not set
@@ -37,7 +38,6 @@
 # CONFIG_PARTITION_UUIDS is not set
 # CONFIG_SPL_PARTITION_UUIDS is not set
 CONFIG_SPL_OF_TRANSLATE=y
-CONFIG_SCSI=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_SDMA=y
 CONFIG_MMC_SDHCI_MV=y
@@ -45,6 +45,7 @@
 CONFIG_SPI_FLASH_MACRONIX=y
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_PCI=y
+CONFIG_SCSI=y
 CONFIG_DEBUG_UART_BASE=0xd0012000
 CONFIG_DEBUG_UART_CLOCK=250000000
 CONFIG_DEBUG_UART_SHIFT=2