ARC: Move ENV_SIZE and ENV_OFFSET to Kconfig

Join the party of some ARM boards and drop more
items from include/configs/xxx.h.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/tb100_defconfig b/configs/tb100_defconfig
index f30053d..e3837d9 100644
--- a/configs/tb100_defconfig
+++ b/configs/tb100_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARC=y
 CONFIG_TARGET_TB100=y
 CONFIG_SYS_TEXT_BASE=0x84000000
+CONFIG_ENV_SIZE=0x800
 CONFIG_SYS_CLK_FREQ=500000000
 CONFIG_BOOTDELAY=3
 CONFIG_USE_BOOTARGS=y