ci: pull trusted-firmware-m repo on Travis run

Update volume maps so local directories in the Travis VM map correctly
to the Docker expected PATH for script running. Misc cleanups.

Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
diff --git a/ci/fih-tests_run.sh b/ci/fih-tests_run.sh
index 7948a3e..80bbf16 100755
--- a/ci/fih-tests_run.sh
+++ b/ci/fih-tests_run.sh
@@ -16,8 +16,14 @@
 
 set -e
 
+pushd .. &&\
+   git clone https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git &&\
+   pushd trusted-firmware-m &&\
+   git checkout 8501b37db8e038ce39eb7f1039a514edea92c96e &&\
+   popd
+
 if test -z "$FIH_LEVEL"; then
-    docker run mcuboot/fih-test /bin/sh -c '/root/execute_test.sh $0 $1 $2' $SKIP_SIZE $BUILD_TYPE $DAMAGE_TYPE
+    docker run --rm -v $(pwd):/root/work/tfm:rw,z mcuboot/fih-test /bin/sh -c '/root/work/tfm/mcuboot/ci/fih_test_docker/execute_test.sh $0 $1 $2' $SKIP_SIZE $BUILD_TYPE $DAMAGE_TYPE
 else
-    docker run mcuboot/fih-test /bin/sh -c '/root/execute_test.sh $0 $1 $2 $3' $SKIP_SIZE $BUILD_TYPE $DAMAGE_TYPE $FIH_LEVEL
-fi
\ No newline at end of file
+    docker run --rm -v $(pwd):/root/work/tfm:rw,z mcuboot/fih-test /bin/sh -c '/root/work/tfm/mcuboot/ci/fih_test_docker/execute_test.sh $0 $1 $2 $3' $SKIP_SIZE $BUILD_TYPE $DAMAGE_TYPE $FIH_LEVEL
+fi
diff --git a/ci/fih_test_docker/execute_test.sh b/ci/fih_test_docker/execute_test.sh
index 7b09ecd..9193564 100755
--- a/ci/fih_test_docker/execute_test.sh
+++ b/ci/fih_test_docker/execute_test.sh
@@ -26,8 +26,6 @@
 DAMAGE_TYPE=$3
 FIH_LEVEL=$4
 
-source ~/.bashrc
-
 if test -z "$FIH_LEVEL"; then
     # Use the default level
     CMAKE_FIH_LEVEL=""