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/trimslice_defconfig b/configs/trimslice_defconfig
index cb42ac5..a904e4b 100644
--- a/configs/trimslice_defconfig
+++ b/configs/trimslice_defconfig
@@ -4,6 +4,7 @@
CONFIG_TARGET_TRIMSLICE=y
CONFIG_DEFAULT_DEVICE_TREE="tegra20-trimslice"
CONFIG_OF_SYSTEM_SETUP=y
+CONFIG_ENV_IS_IN_SPI_FLASH=y
CONFIG_CONSOLE_MUX=y
CONFIG_SYS_STDIO_DEREGISTER=y
CONFIG_SYS_PROMPT="Tegra20 (TrimSlice) # "