Use android_get_control_socket from the rustutils crate

prng_seeder had its own rust wrapper for android_get_control_socket
(from libcutils). Let's switch to the one in the rustutils crate since
it provides a common implementation. Plus, the implementation is a bit
safer because it ensures that the socket is exclusively owned by using
the recently added rustutils::inherited_fd module.

Bug: 243500154
Test: build
Merged-In: I70318dc8b197a93d0f791ac968fc03b7aaf2efaa
Change-Id: I70318dc8b197a93d0f791ac968fc03b7aaf2efaa
diff --git a/prng_seeder/src/main.rs b/prng_seeder/src/main.rs
index cb7f38d..d112d61 100644
--- a/prng_seeder/src/main.rs
+++ b/prng_seeder/src/main.rs
@@ -18,7 +18,6 @@
 //! by init.
 
 mod conditioner;
-mod cutils_socket;
 mod drbg;
 
 use std::{
@@ -70,6 +69,9 @@
 }
 
 fn setup() -> Result<(ConditionerBuilder, UnixListener)> {
+    // SAFETY: nobody has taken ownership of the inherited FDs yet.
+    unsafe { rustutils::inherited_fd::init_once() }
+        .context("In setup, failed to own inherited FDs")?;
     configure_logging()?;
     let cli = Cli::try_parse()?;
     // SAFETY: Nothing else sets the signal handler, so either it was set here or it is the default.
@@ -78,8 +80,9 @@
 
     let listener = match cli.socket {
         Some(path) => get_socket(path.as_path())?,
-        None => cutils_socket::android_get_control_socket("prng_seeder")
-            .context("In setup, calling android_get_control_socket")?,
+        None => rustutils::sockets::android_get_control_socket("prng_seeder")
+            .context("In setup, calling android_get_control_socket")?
+            .into(),
     };
     let hwrng = std::fs::File::open(&cli.source)
         .with_context(|| format!("Unable to open hwrng {}", cli.source.display()))?;