ls2080ardb: remove dhcp function from env as boot source

Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/include/configs/ls2080ardb.h b/include/configs/ls2080ardb.h
index 3d53a69..05c02df 100644
--- a/include/configs/ls2080ardb.h
+++ b/include/configs/ls2080ardb.h
@@ -323,8 +323,7 @@
 #define BOOT_TARGET_DEVICES(func) \
 	func(USB, usb, 0) \
 	func(MMC, mmc, 0) \
-	func(SCSI, scsi, 0) \
-	func(DHCP, dhcp, na)
+	func(SCSI, scsi, 0)
 #include <config_distro_bootcmd.h>
 
 #ifdef CONFIG_QSPI_BOOT