dri3: Add missing libdrm dependency in Makefile.am

Fixes: 0ce93e5b "dri3: Include dix-config.h instead of
                     xorg-config.h"
Signed-off-by: Dor Askayo <dor.askayo@gmail.com>
4 jobs for dri3-missing-dependency in 6 minutes and 8 seconds (queued for 1 second)
Status Job ID Name Coverage
  Docker Image
passed #4697602
debian-testing

00:00:16

 
  Build And Test
passed #4697603
autotools

00:05:52

passed #4697604
meson

00:01:50

passed #4697605
meson-noglamor

00:01:29