doc: add KNI behaviour change in release notes
Commit
89397a01ce4a ("kni: set default carrier state of interface")
changes the KNI interface default carrier status. Which prevents traffic
flow by default and may break some existing usage / testing.
Document this behavior change in release notes.
Fixes:
c6fd54f28c24 ("kni: add function to set link state on kernel interface")
Fixes:
89397a01ce4a ("kni: set default carrier state of interface")
Fixes:
724beb913b44 ("examples/kni: monitor and update link state continually")
Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>