daq: add necessary dependencies on host-flex and host-bison

daq depends on flex and bison to be configured.

Fixes:
http://autobuild.buildroot.net/results/43da4ae3b7fc26e6712d369d4d030954d0d85149
http://autobuild.buildroot.net/results/0fc2bcf9da758f427adf2fddca8ad1dace6a080e
http://autobuild.buildroot.net/results/7411ac4ae5bef71b78c69b680de2b72f389ad2ee


... and many more.

Signed-off-by: Sergio Prado <sergio.prado@e-labworks.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>