linux: do not allow selecting RTAI for latest/cip kernels
RTAI is only supported on very specific kernel versions that are
different from the latest/cip kernel versions, so we should not
allow selecting RTAI when building with latest/cip kernels.
Fixes:
- http://autobuild.buildroot.net/results/412/412492e19b41f95ff2445df6b7564cb0fa48873b
- http://autobuild.buildroot.net/results/32c/32c9ffd8e965eb690ca0b0471e9c1cc16bb2fa66
- http://autobuild.buildroot.net/results/0bc/0bc178dcb11aa23e5f8bf75c958d8a56c6c38964
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit e5ff1de64e60f6ab2faaa751378fce0ec6bf1010)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>