depends: update LD64_VERSION to 711

I forgot to do this in 7d58152.

Author: fanquake

depends/hosts/darwin.mk

@@ -2,7 +2,7 @@ OSX_MIN_VERSION=11.0
 OSX_SDK_VERSION=11.0
 XCODE_VERSION=12.2
 XCODE_BUILD_ID=12B45b
-LD64_VERSION=609
+LD64_VERSION=711
 
 OSX_SDK=$(SDK_PATH)/Xcode-$(XCODE_VERSION)-$(XCODE_BUILD_ID)-extracted-SDK-with-libcxx-headers