ARC: HSDK: Enable SPI flash support

HSDK board has sst26wf016 SPI flash IC which we want to support.

Add SPI controller, CS-gpio and SPI flash nodes to hsdk device tree.
Enable corresponding options in hsdk defconfig.

For SPI write functionality to work we need [1] which
adds support of sst26xxx ICs.

[1] https://patchwork.ozlabs.org/project/uboot/list/?series=35796

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
diff --git a/configs/hsdk_defconfig b/configs/hsdk_defconfig
index c72ee2d..476ce6a 100644
--- a/configs/hsdk_defconfig
+++ b/configs/hsdk_defconfig
@@ -12,6 +12,8 @@
 CONFIG_CMD_ENV_FLAGS=y
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_MMC=y
+CONFIG_CMD_SF=y
+CONFIG_CMD_SPI=y
 CONFIG_CMD_USB=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_CMD_DHCP=y
@@ -29,12 +31,19 @@
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_DM=y
 CONFIG_CLK_HSDK=y
+CONFIG_DM_GPIO=y
+CONFIG_HSDK_CREG_GPIO=y
 CONFIG_MMC=y
 CONFIG_MMC_DW=y
+CONFIG_DM_SPI_FLASH=y
+CONFIG_SPI_FLASH=y
+CONFIG_SPI_FLASH_SST=y
 CONFIG_DM_ETH=y
 CONFIG_ETH_DESIGNWARE=y
 CONFIG_DM_SERIAL=y
 CONFIG_SYS_NS16550=y
+CONFIG_DM_SPI=y
+CONFIG_DESIGNWARE_SPI=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
 CONFIG_USB_EHCI_HCD=y