vlc-debian-llvm-mingw: Don't bother building cmake

We're using sid as a base, which packages cmake 3.18.4
2 jobs for master in 51 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
failed #480275
build

00:00:51

failed #480177
build

00:50:32

 
Name Stage Failure
failed
build Build There has been a runner system failure, please try again
Pulling docker image docker:19.03.1-dind ...
ERROR: Preparation failed: Error response from daemon: Get https://registry-1.docker.io/v2/: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers) (docker.go:196:15s)
Will be retried in 3s ...
Using Docker executor with image docker:19.03.1 ...
Starting service docker:19.03.1-dind ...
Pulling docker image docker:19.03.1-dind ...
ERROR: Preparation failed: Error response from daemon: Get https://registry-1.docker.io/v2/: dial tcp: lookup registry-1.docker.io on 10.10.1.1:53: read udp 10.10.1.201:57769->10.10.1.1:53: i/o timeout (docker.go:196:1s)
Will be retried in 3s ...
ERROR: Job failed (system failure): Error response from daemon: Get https://registry-1.docker.io/v2/: dial tcp: lookup registry-1.docker.io on 10.10.1.1:53: read udp 10.10.1.201:57769->10.10.1.1:53: i/o timeout (docker.go:196:1s)