thunar-volman: Add udev to DEPENDS

With fresh tmp-dir bitbake thunar-volman failed with

| checking for gudev-1.0 >= 145... not found
| *** The required package gudev-1.0 was not found on your system.
| *** Please install gudev-1.0 (atleast version 145) or adjust
| *** the PKG_CONFIG_PATH environment variable if you
| *** installed the package in a nonstandard prefix so that
| *** pkg-config is able to find it.
| + bbfatal 'oe_runconf failed'

Signed-off-by: Andreas Müller <schnitzeltony@gmx.de>
Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>