Adds environment variable support to Docker run script

Updates the Docker run script to pass environment variables
(CMAKE_BUILD_TYPE, PRIVATE_KEY_OPTION, USE_XARGS) to the container.
Improves configurability and flexibility during container runtime.

Signed-off-by: Christopher Turner <christopher.g.turner@intel.com>

Author: cgturner1

scripts/docker-run.sh

@@ -35,7 +35,7 @@ test "$(id -u)" = 1000 ||
 set -x
 docker run -i -v "${SOF_TOP}":/home/sof/work/sof.git \
 	-v "${SOF_TOP}":/home/sof/work/sof-bind-mount-DO-NOT-DELETE \
-	--user 1000:1000
+	--user 1000:1000 \
 	--env CMAKE_BUILD_TYPE \
 	--env PRIVATE_KEY_OPTION \
 	--env USE_XARGS \