Enable AOT build for linux-riscv64-musl (#2258)

Author: ntkme

.github/workflows/build-linux-musl.yml

@@ -26,9 +26,8 @@ jobs:
           # https://gitlab.com/qemu-project/qemu/-/issues/1729
           - arch: arm
             platform: linux/amd64 # linux/arm/v7
-          # There is no docker image for riscv64 dart-sdk, build kernel snapshot instead.
           - arch: riscv64
-            platform: linux/amd64 # linux/riscv64
+            platform: linux/riscv64
 
     steps:
       - uses: actions/checkout@v4