ARC: HSDK: Add platform-specific commands

This patch add support of hsdk platform-specific commands:

hsdk_clock set - set clock from axi_freq, cpu_freq and tun_freq
environment variables/command line arguments

hsdk_clock get - save clock frequencies to axi_freq, cpu_freq
and tun_freq environment variables

hsdk_clock print - show CPU, AXI, DDR and TUNNEL current
clock frequencies.

hsdk_clock print_all - show all currently used clock frequencies.

hsdk_init - setup board HW in one of pre-defined configuration
(hsdk_hs34 / hsdk_hs36 / hsdk_hs36_ccm / hsdk_hs38 /
hsdk_hs38_ccm / hsdk_hs38x2 / hsdk_hs38x3 / hsdk_hs38x4)

hsdk_go - run baremetal application on hsdk configured
by hsdk_init command.

This patch changes default behaviour of 'bootm' command:
now we are able to set number of CPUs to be kicked by setting
'core_mask' environment variable before 'bootm' command run.

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 11cb7e0..c72ee2d 100644
--- a/configs/hsdk_defconfig
+++ b/configs/hsdk_defconfig
@@ -7,13 +7,16 @@
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="console=ttyS0,115200n8"
 CONFIG_BOARD_EARLY_INIT_F=y
+CONFIG_HUSH_PARSER=y
 CONFIG_SYS_PROMPT="hsdk# "
+CONFIG_CMD_ENV_FLAGS=y
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_MMC=y
 CONFIG_CMD_USB=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_CMD_DHCP=y
 CONFIG_CMD_PING=y
+CONFIG_CMD_CACHE=y
 CONFIG_CMD_EXT2=y
 CONFIG_CMD_EXT4=y
 CONFIG_CMD_EXT4_WRITE=y
@@ -25,6 +28,7 @@
 CONFIG_ENV_FAT_DEVICE_AND_PART="0:1"
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_DM=y
+CONFIG_CLK_HSDK=y
 CONFIG_MMC=y
 CONFIG_MMC_DW=y
 CONFIG_DM_ETH=y