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/theadorable_debug_defconfig b/configs/theadorable_debug_defconfig
index 9e8523d..43b7a70 100644
--- a/configs/theadorable_debug_defconfig
+++ b/configs/theadorable_debug_defconfig
@@ -29,6 +29,7 @@
 CONFIG_DISPLAY_BOARDINFO_LATE=y
 CONFIG_SPL_I2C=y
 CONFIG_HUSH_PARSER=y
+CONFIG_SYS_MAXARGS=32
 CONFIG_CMD_BOOTZ=y
 CONFIG_CMD_GPIO=y
 CONFIG_CMD_I2C=y