libv4l: fix missing libintl linking

Add missing libintl linking to utils/dvb and utils/keytable (patch
Makefile.am and do autoreconf with host-gettext dependency).

Patch submitted upstream (see [2]).

Add proper gettext dependency for v4l-utils option.

Fixes [1]:
 dvb-format-convert.o: In function `parse_opt':
 dvb-format-convert.c:(.text+0x46): undefined reference to `libintl_gettext'

[1] http://autobuild.buildroot.net/results/40a/40a12c0d1746dcc51e4f221eefbbf31bd427cac8
[2] http://permalink.gmane.org/gmane.linux.drivers.video-input-infrastructure/95883



Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>