linux.inc: enable autofs

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
linux-ti 3.14: fix up kernel fragments for DRM

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
linux-ti 3.14: tweak beaglebone defconfig

It boots again, but btrfs is disabled.

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>