arm: mvebu: ds414: Auto-populate env if appropriate

Define a misc_init_r() which calls "syno populate_env" if the
environment seems incomplete (or default), indicated by missing
"ethaddr" variable. With this in place, no random MAC address fallback
is needed anymore.

Signed-off-by: Phil Sutter <phil@nwl.cc>
diff --git a/board/Synology/ds414/cmd_syno.c b/board/Synology/ds414/cmd_syno.c
index a120c31..a62658a 100644
--- a/board/Synology/ds414/cmd_syno.c
+++ b/board/Synology/ds414/cmd_syno.c
@@ -17,12 +17,9 @@
 #include <asm/io.h>
 #include "../drivers/ddr/marvell/axp/ddr3_init.h"
 
-#define ETHADDR_MAX		4
-#define SYNO_SN_TAG		"SN="
-#define SYNO_CHKSUM_TAG		"CHK="
+#include "cmd_syno.h"
 
-
-static int do_syno_populate(int argc, char *const argv[])
+int do_syno_populate(int argc, char *const argv[])
 {
 	unsigned int bus = CONFIG_SF_DEFAULT_BUS;
 	unsigned int cs = CONFIG_SF_DEFAULT_CS;
@@ -57,7 +54,7 @@
 		goto out_unmap;
 	}
 
-	for (n = 0; n < ETHADDR_MAX; n++) {
+	for (n = 0; n < SYNO_ETHADDR_MAX; n++) {
 		char ethaddr[ETH_ALEN];
 		int i, sum = 0;
 		unsigned char csum = 0;