Merge branch 'dockerfile_incremental' into 'develop'

Proposal to use incremental builds

See merge request oai/cn5g/oai-cn5g-smf!170

docker/Dockerfile.smf.rhel8

@@ -64,12 +64,16 @@ RUN git config --global https.postBuffer 123289600 && \
 
 # Copying source code
 WORKDIR /openair-smf
-COPY . /openair-smf
+COPY ./build/scripts /openair-smf/build/scripts
+COPY ./build/smf/CMakeLists.txt /openair-smf/build/smf/CMakeLists.txt
+COPY ./build/cmake_modules /openair-smf/cmake_modules
 
 # Installing all the needed libraries/packages to build and run SMF
 WORKDIR /openair-smf/build/scripts
 RUN ./build_smf --install-deps --force
 
+COPY . /openair-smf
+
 # Building SMF
 WORKDIR /openair-smf/build/scripts
 RUN ldconfig && \

docker/Dockerfile.smf.ubuntu

@@ -49,13 +49,17 @@ RUN git config --global https.postBuffer 123289600 && \
 
 # Copying source code
 WORKDIR /openair-smf
-COPY . /openair-smf
+COPY ./build/scripts /openair-smf/build/scripts
+COPY ./build/smf/CMakeLists.txt /openair-smf/build/smf/CMakeLists.txt
+COPY ./build/cmake_modules /openair-smf/cmake_modules
 
 # Installing all the needed libraries/packages to build and run SMF
 WORKDIR /openair-smf/build/scripts
 RUN ./build_smf --install-deps --force && \
     cp -Rf /openair-smf/build/ext /openair-smf-ext-ref
 
+COPY . /openair-smf
+
 #---------------------------------------------------------------------
 # BUILDER IMAGE
 #---------------------------------------------------------------------