ifupdown: Launch udhcpc the same we way always do it

In case the port is not in a forwarding state.. don't just
give up but background and move on. This appears to be needed
for the odu to acquire a lease when STP is used.

recipes-extra/ifupdown/files/busybox-yocto-compat.patch

@@ -68,3 +68,16 @@ Index: ifupdown-0.7.52/execute.c
      out = parse(command, ifd);
      if (!out) {
          return 0;
+Index: ifupdown-0.7.52/inet.defn
+===================================================================
+--- ifupdown-0.7.52.orig/inet.defn
++++ ifupdown-0.7.52/inet.defn
+@@ -89,7 +89,7 @@ method dhcp
+         elsif (execable("/sbin/dhclient3"))
+     pump -i %iface% [[-h %hostname%]] [[-l %leasehours%]] \
+         elsif (execable("/sbin/pump") && mylinuxver() >= mylinux(2,1,100))
+-    udhcpc -n -p /run/udhcpc.%iface%.pid -i %iface% [[-x hostname:%hostname%]] \
++    udhcpc -R -b -p /run/udhcpc.%iface%.pid -i %iface% [[-x hostname:%hostname%]] \
+         elsif (execable("/sbin/udhcpc") && mylinuxver() >= mylinux(2,2,0))
+     dhcpcd [[-h %hostname%]] [[-i %vendor%]] [[-I %client%]] \
+            [[-l %leasetime%]] %iface% \

recipes-extra/ifupdown/ifupdown_0.7.52.bb

@@ -14,7 +14,7 @@ SRC_URI[sha256sum] = "8a0647c59ee0606f5da9205c5b3c5b000fea98fe39348f6bb2cba5fecf
 
 CFLAGS += "-D'IFUPDOWN_VERSION="0.7"'"
 
-PR = "r1"
+PR = "r2"
 
 do_configure() {
 	chmod a+rx makecdep.sh makenwdep.sh