Fix compilation on macOS

This fixes the compilation on x86_64 and Arm (M1) machines
running macOS.

Reference: mischov/meeseeks_html5ever#46

Author: philss

native/html5ever_nif/.cargo/config

@@ -0,0 +1,11 @@
+[target.x86_64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]
+
+[target.aarch64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]