busybox: Fix path to ifplugd
busybox: Fix path to ifplugd

On daisy, ifplugd changed from /usr/bin/ifplugd to /usr/sbin/ifplugd.
Updated script to reflect the change.

Acked-by: Ken Sharp <e6c8ad8f54d15df4645e8aaf3f7a209bc3688570@ni.com>
Acked-by: Rich Tollerton <67c688e7f7482ba5c4ebe3d70bc77594748182a6@ni.com>
Acked-by: Ben Shelton <873d2944fc7a954ed322314738197137e10de387@ni.com>
Signed-off-by: Alejandro del Castillo <c09cbcd73cd5840fe009d82a3ad13af11b4d7b46@ni.com>

ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt,ni/meta-nilrt