ci: split download into its own step

Move download into its own step and only run it on a single target
so we don't have issues with multiple steps trying to upload the same
artifacts.

Signed-off-by: Kumar Gala <[email protected]>

Author: galak

.buildkite/download.yml

@@ -0,0 +1,19 @@
+steps:
+  - label: "download-sources"
+    key: "download-sources"
+    depends_on: "linux-x86_64-crosstool-cmake"
+    command:
+    - buildkite-agent artifact download crosstool.linux.x86_64.tar.bz2 .
+    - tar xf crosstool.linux.x86_64.tar.bz2
+    - export CT_ONLY_DOWNLOAD=y
+    - ./go.sh arm
+    - buildkite-agent artifact upload "build/output/sources/*"
+    env:
+      BUILDKITE_CLEAN_CHECKOUT: "true"
+    plugins:
+      - docker#v3.5.0:
+          image: "zephyrprojectrtos/sdk-build:v1.0.1"
+          propagate-environment: true
+          user: buildkite-agent
+    agents:
+    - "queue=sdk-ng-x86_64"

.buildkite/pipeline-template.yml

@@ -6,9 +6,6 @@ steps:
     - buildkite-agent artifact upload cmake.$OS.$MACHINE.tar.bz2
     - ./go.sh crosstool
     - buildkite-agent artifact upload crosstool.$OS.$MACHINE.tar.bz2
-    - export CT_ONLY_DOWNLOAD=y
-    - ./go.sh arm
-    - buildkite-agent artifact upload "build/output/sources/*"
     env:
       BUILDKITE_CLEAN_CHECKOUT: "true"
     plugins:
@@ -21,7 +18,7 @@ steps:
 
   - label: "$OS-$MACHINE"
     key: "$OS-$MACHINE"
-    depends_on: "$OS-$MACHINE-crosstool-cmake"
+    depends_on: "download-sources"
     command:
     - >
       case "$${BUILDKITE_PARALLEL_JOB}" in