Implement transfer function for interpreting nullptr, address_of (&) operator, comparison between pointers.

PiperOrigin-RevId: 453859336
diff --git a/nullability_verification/BUILD b/nullability_verification/BUILD
index fb9700b..82f321b 100644
--- a/nullability_verification/BUILD
+++ b/nullability_verification/BUILD
@@ -14,8 +14,8 @@
     srcs = ["pointer_nullability_matchers.cc"],
     hdrs = ["pointer_nullability_matchers.h"],
     deps = [
+        "@llvm-project//clang:ast",
         "@llvm-project//clang:ast_matchers",
-        "@llvm-project//llvm:Support",
     ],
 )