buildroot

emlog: remove linux dependency

The dependency on linux is automatically added by the kernel-module
infrastructure, so there is no need to explicit add it in the emlog
package.

Thanks to Arnout for spotting the issue.

Reported-by: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>