RPM build fix (reverted CI changes which will need to be un-reverted or made conditional) and vendor Rust dependencies to make builds much faster in any CI system.

zeroidc/vendor/cbindgen/tests/rust/simplify_option_ptr.rs

@@ -0,0 +1,28 @@
+
+struct Opaque();
+
+#[repr(C)]
+struct Foo {
+    x: Option<&Opaque>,
+    y: Option<&mut Opaque>,
+    z: Option<fn () -> ()>,
+    zz: *mut Option<fn () -> ()>,
+}
+
+#[repr(C)]
+union Bar {
+    x: Option<&Opaque>,
+    y: Option<&mut Opaque>,
+    z: Option<fn () -> ()>,
+    zz: *mut Option<fn () -> ()>,
+}
+
+#[no_mangle]
+pub extern "C" fn root(
+	a: Option<&Opaque>,
+    b: Option<&mut Opaque>,
+    c: Foo,
+    d: Bar,
+    e: *mut Option<*mut Opaque>,
+    f: extern "C" fn(Option<&Opaque>),
+) { }