rpb: add pam in DISTRO_FEATURES
rpb: add pam in DISTRO_FEATURES

Signed-off-by: Nicolas Dechesne <05fca36dfcf68f7e1c9eaf62b074676ab50a133b@linaro.org>

96boards/meta-rpb,fboudra/meta-rpb,96boards/meta-rpb,fboudra/meta-rpb,fboudra/meta-rpb