gitlab-ci: Rename container install scripts to match job names (better)

Cleans up .gitlab-ci/ a little, and allows using a single DEBIAN_EXEC
line for all container jobs.

v2:
* Use lava_arm.sh instead of arm_lava.sh for consistency with v2 of the
  previous change

Reviewed-by: Eric Anholt <eric@anholt.net> # v1
Reviewed-by: Eric Engestrom <eric@engestrom.ch>

.gitlab-ci/container/lava_arm.sh

@@ -184,4 +184,3 @@ chroot /artifacts/rootfs sh /create-rootfs.sh
 rm /artifacts/rootfs/bin/qemu-arm-static
 rm /artifacts/rootfs/bin/qemu-aarch64-static
 rm /artifacts/rootfs/create-rootfs.sh
-

.gitlab-ci/lava-gitlab-ci.yml

@@ -36,7 +36,7 @@ include:
                   DEFCONFIG=${DEFCONFIG}
                   DEVICE_TREES="${DEVICE_TREES}"
                   KERNEL_IMAGE_NAME=${KERNEL_IMAGE_NAME}
-                  bash .gitlab-ci/lava-debian-install.sh'
+                  bash .gitlab-ci/container/lava_arm.sh'
     DEBIAN_VERSION: ${LAVA_DEBIAN_VERSION}
 
 lava_armhf: