buildroot

firejail: fix logic for comment

firejail depends on !uClibc, so the "firejail needs !uClibc" comment
should be displayed when we do have uClibc. Right now the logic is just
the other way around, so flip it.

Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>