package/busybox: add -O staticroutes options to udhcpc

udhcpc default script can handle staticroutes but it is missing from the
default ifupdown options.

Signed-off-by: Remi Jouannet <remi.jouannet@outscale.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/busybox/busybox.config

@@ -1022,7 +1022,7 @@ CONFIG_UDHCP_DEBUG=0
 CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS=80
 CONFIG_FEATURE_UDHCP_RFC3397=y
 CONFIG_FEATURE_UDHCP_8021Q=y
-CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS="-t1 -A3 -b -R -O search"
+CONFIG_IFUPDOWN_UDHCPC_CMD_OPTIONS="-t1 -A3 -b -R -O search -O staticroutes"
 
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