feat: support risc-v platform

Signed-off-by: Derek Su <derek.su@suse.com>

.github/workflows/build.yml

@@ -88,7 +88,7 @@ jobs:
       with:
         context: ./
         push: true
-        platforms: linux/amd64,linux/arm64, linux/arm
+        platforms: linux/amd64,linux/arm64,linux/arm,linux/riscv64
         tags: rancher/local-path-provisioner:${{ env.branch }}-head
         file: package/Dockerfile
 
@@ -98,6 +98,6 @@ jobs:
       with:
         context: ./
         push: true
-        platforms: linux/amd64,linux/arm64, linux/arm
+        platforms: linux/amd64,linux/arm64,linux/arm,linux/riscv64
         tags: rancher/local-path-provisioner:${{ github.ref_name }}
         file: package/Dockerfile