feat: initial support for riscv64 (#2366)

* feat: initial support for riscv64

* use enable for riscv64

* Apply review suggestion

Co-authored-by: Joe Rickerby <joerick@mac.com>

* update documentation

---------

Co-authored-by: Joe Rickerby <joerick@mac.com>

bin/generate_schema.py

@@ -31,6 +31,7 @@ $defs:
       - cpython-freethreading
       - cpython-prerelease
       - pypy
+      - cpython-experimental-riscv64
   description: A Python version or flavor to enable.
 additionalProperties: false
 description: cibuildwheel's settings.
@@ -157,6 +158,9 @@ properties:
   manylinux-pypy_x86_64-image:
     type: string
     description: Specify alternative manylinux / musllinux container images
+  manylinux-riscv64-image:
+    type: string
+    description: Specify alternative manylinux / musllinux container images
   manylinux-s390x-image:
     type: string
     description: Specify alternative manylinux / musllinux container images
@@ -175,6 +179,9 @@ properties:
   musllinux-ppc64le-image:
     type: string
     description: Specify alternative manylinux / musllinux container images
+  musllinux-riscv64-image:
+    type: string
+    description: Specify alternative manylinux / musllinux container images
   musllinux-s390x-image:
     type: string
     description: Specify alternative manylinux / musllinux container images

bin/update_docker.py

@@ -116,5 +116,8 @@ for image in images:
             suffix = f"_{platform.removeprefix('pypy_')}"
         config[platform][image.manylinux_version] = f"{image.image_name}{suffix}:{tag_name}"
 
+if not config.has_section("riscv64"):
+    config["riscv64"] = {}
+
 with open(RESOURCES / "pinned_docker_images.cfg", "w") as f:
     config.write(f)