am335x, guardian: set environment variable autoload to no

autoload: if set to "no" then rarpb, bootp or dhcp commands will
just perform a configuration lookup from the BOOTP / DHCP server,
but not try to load any image using TFTP

Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210611161350.2141-8-Gireesh.Hiremath@in.bosch.com

include/configs/am335x_guardian.h

@@ -58,9 +58,9 @@
 	MEM_LAYOUT_ENV_SETTINGS \
 	BOOTENV \
 	GUARDIAN_DEFAULT_PROD_ENV \
+	"autoload=no\0" \
 	"bootubivol=rootfs\0" \
 	"distro_bootcmd=" \
-		"setenv autoload no; " \
 		"setenv rootflags \"bulk_read,chk_data_crc\"; " \
 		"setenv ethact usb_ether; " \
 		"if test \"${swi_status}\" -eq 1; then " \