layer.conf: Mark it dunfell (3.1) compatible
layer.conf: Mark it dunfell (3.1) compatible

Signed-off-by: Khem Raj <729d64b6f67515e258459a5f6d20ec88b2caf8df@gmail.com>

ndechesne/meta-qualcomm,ndechesne/meta-qcom,ndechesne/meta-qcom,ndechesne/meta-qcom