board: siemens: iot2050: Fix mistake in list of writable env vars

This prevented to set m2_manual_config - as evaluated by
m2_connector_setup - under strict configurations for secure boot.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
diff --git a/include/configs/iot2050.h b/include/configs/iot2050.h
index 94a9c76..0f92e0d 100644
--- a/include/configs/iot2050.h
+++ b/include/configs/iot2050.h
@@ -39,7 +39,7 @@
 #define CFG_ENV_FLAGS_LIST_STATIC					\
 	"board_uuid:sw,board_name:sw,board_serial:sw,board_a5e:sw,"	\
 	"mlfb:sw,fw_version:sw,seboot_version:sw,"			\
-	"m2_manuel_config:sw,"						\
+	"m2_manual_config:sw,"						\
 	"eth1addr:mw,eth2addr:mw,watchdog_timeout_ms:dw,boot_targets:sw"
 #endif