Convert CONFIG_SYS_MAXARGS to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_MAXARGS

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/smegw01_defconfig b/configs/smegw01_defconfig
index d5d1791..7231642 100644
--- a/configs/smegw01_defconfig
+++ b/configs/smegw01_defconfig
@@ -20,6 +20,7 @@
 CONFIG_USE_BOOTCOMMAND=y
 CONFIG_BOOTCOMMAND="if run loadimage; then run mmcboot; fi; "
 CONFIG_HUSH_PARSER=y
+CONFIG_SYS_MAXARGS=32
 # CONFIG_CMD_BOOTD is not set
 CONFIG_CMD_BOOTZ=y
 # CONFIG_CMD_IMI is not set