package/eudev: fix build with kernel < 3.11

package/eudev: fix build with kernel < 3.11

As explained in issue 6267 of systemd [1], Linux < 3.11 does not provide
definitions for BTN_DPAD_{UP,RIGHT}, which were introduced in [2].

So, add a patch to fix this issue.

[1] https://github.com/systemd/systemd/pull/6267
[2] https://github.com/torvalds/linux/commit/9ee27487127461b5cf71670b708ed5b2b8da568c

Fixes:

- http://autobuild.buildroot.net/results/e9d94084be8ed3296ba63cffdb9d69ffcc3b7140/
- http://autobuild.buildroot.net/results/d9c5ec07bfbde1fab62991bb509c2f90af1cb3f4/

Signed-off-by: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>