Build switch target using the devkita64 docker image

.gitlab-ci.yml

@@ -118,10 +118,10 @@ job_gp2x:
 
 job_switch:
     stage: build
+    image: devkitpro/devkita64
     before_script:
-        - apt-get update -qq && apt-get install -y -qq zip
-        - "sh ./.install-switch-toolchain.sh"
-        - "source /etc/profile.d/devkit-env.sh"
+        - apt-get update -qq &&  apt-get install -y -qq build-essential libpng-dev zip dos2unix
+        - "export PATH=$PATH:$DEVKITPRO/portlibs/switch/bin"
     script:
         - "SWITCH=1 make -j2 grafx2 || exit 1"
         - "SWITCH=1 make ziprelease || exit 1"