Add armv7-unknown-linux-gnueabihf alias for backwards compatibility (#3410)

Author: hofbi

rust/platform/platform.bzl

@@ -66,6 +66,12 @@ def declare_config_settings():
             constraint_values = triple_to_constraint_set(triple),
         )
 
+    native.alias(
+        name = "armv7-unknown-linux-gnueabihf",
+        actual = ":armv7-unknown-linux-gnueabi",
+        deprecation = "Use `@rules_rust//rust/platform:armv7-unknown-linux-gnueabi` instead.",
+    )
+
     # Add alias for wasm to maintain backwards compatibility.
     native.alias(
         name = "wasm32-wasi",