Include bindgen generated file via a build time env var, this plays nicer with other build systems like Soong and Gn.

Change-Id: I42e40da22dd243796cd735e09a9821cc2d114200
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/58785
Reviewed-by: Bob Beck <bbe@google.com>
Commit-Queue: Bob Beck <bbe@google.com>
diff --git a/rust/bssl-sys/src/lib.rs b/rust/bssl-sys/src/lib.rs
index d8c2c00..51ba2cf 100644
--- a/rust/bssl-sys/src/lib.rs
+++ b/rust/bssl-sys/src/lib.rs
@@ -2,8 +2,8 @@
 #![allow(non_camel_case_types)]
 #![allow(non_snake_case)]
 
-// populated by cmake
-${INCLUDES}
+// Set in build.rs
+include!(env!("BINDGEN_RS_FILE"));
 
 pub fn ERR_GET_LIB(packed_error: u32) -> i32 {
     unsafe { ERR_GET_LIB_RUST(packed_error) }
@@ -18,5 +18,7 @@
 }
 
 pub fn init() {
-    unsafe { CRYPTO_library_init(); }
+    unsafe {
+        CRYPTO_library_init();
+    }
 }