ci: docker: remove source repos from fih-test

Update Dockerfile to only build a distro and required tooling, avoiding
adding source repositories, including tfm and mcuboot, so that it can be
reused without the need to rebuild all the time.

This should allow pushing the image under mcuboot/fih-test and
pulling+caching in Travis.

Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
diff --git a/ci/fih_test_docker/Dockerfile b/ci/fih_test_docker/docker-build/Dockerfile
similarity index 69%
rename from ci/fih_test_docker/Dockerfile
rename to ci/fih_test_docker/docker-build/Dockerfile
index 3ee021a..f76c515 100644
--- a/ci/fih_test_docker/Dockerfile
+++ b/ci/fih_test_docker/docker-build/Dockerfile
@@ -31,24 +31,13 @@
 RUN \
     # installing python packages
     python3 -m pip install \
-        imgtool==1.6.0 \
+        imgtool==1.7.0 \
         Jinja2==2.10 \
         PyYAML==3.12 \
         pyasn1==0.1.9
 
-# Clone TF-M and dependencies
-RUN mkdir -p /root/work/tfm &&\
-    cd /root/work/tfm  &&\
-    git clone https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git &&\
-    cd trusted-firmware-m &&\
-    git checkout 8501b37db8e038ce39eb7f1039a514edea92c96e &&\
-    cd .. &&\
-    mkdir mcuboot
-
-# Copy the test execution script to the image
-COPY execute_test.sh /root
-# copy the MCUBoot under test to the image
-COPY mcuboot /root/work/tfm/mcuboot
+# Add tfm work directory
+RUN mkdir -p /root/work/tfm
 
 # run the command
-CMD ["bash"]
\ No newline at end of file
+CMD ["bash"]
diff --git a/ci/fih_test_docker/build.sh b/ci/fih_test_docker/docker-build/build.sh
similarity index 96%
rename from ci/fih_test_docker/build.sh
rename to ci/fih_test_docker/docker-build/build.sh
index 304362e..d0d00b3 100755
--- a/ci/fih_test_docker/build.sh
+++ b/ci/fih_test_docker/docker-build/build.sh
@@ -27,4 +27,3 @@
 
 image=mcuboot/fih-test
 docker build --pull --tag=$image .
-echo $image > .docker-tag
\ No newline at end of file