External CI: change trigger from amd-master to amd-mainline

Signed-off-by: Su, Daniel <Daniel.Su@amd.com>

[ROCm/ROCR-Runtime commit: 70b44c576c]

projects/rocr-runtime/.azuredevops/rocm-ci.yml

@@ -14,7 +14,7 @@ trigger:
   branches:
     include:
     - amd-staging
-    - amd-master
+    - amd-mainline
   paths:
     exclude:
     - .github
@@ -26,7 +26,7 @@ pr:
   branches:
     include:
     - amd-staging
-    - amd-master
+    - amd-mainline
   paths:
     exclude:
     - .github