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/xilinx_versal_virt_defconfig b/configs/xilinx_versal_virt_defconfig
index 38747ff..d7dda69 100644
--- a/configs/xilinx_versal_virt_defconfig
+++ b/configs/xilinx_versal_virt_defconfig
@@ -22,6 +22,7 @@
 CONFIG_BOARD_EARLY_INIT_R=y
 CONFIG_CLOCKS=y
 CONFIG_SYS_PROMPT="Versal> "
+CONFIG_SYS_MAXARGS=64
 CONFIG_CMD_BOOTMENU=y
 CONFIG_CMD_NVEDIT_EFI=y
 CONFIG_CMD_MEMTEST=y