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/total_compute_defconfig b/configs/total_compute_defconfig
index 826afaa..f380a82 100644
--- a/configs/total_compute_defconfig
+++ b/configs/total_compute_defconfig
@@ -22,6 +22,7 @@
 CONFIG_AVB_BUF_ADDR=0x90000000
 CONFIG_AVB_BUF_SIZE=0x10000000
 CONFIG_SYS_PROMPT="TOTAL_COMPUTE# "
+CONFIG_SYS_MAXARGS=64
 # CONFIG_CMD_CONSOLE is not set
 # CONFIG_CMD_XIMG is not set
 # CONFIG_CMD_EDITENV is not set