Tool to tune system parameters like PoH service priority (#7155)

* New daemon to tune system parameters like PoH service priority

* fixes for Linux

* integrate with poh_service

* fixes

* address review comments

* remove `dead_code` directive

sys-tuner/src/lib.rs

@@ -0,0 +1,10 @@
+use log::*;
+use unix_socket::UnixStream;
+
+pub const SOLANA_SYS_TUNER_PATH: &str = "/tmp/solana-sys-tuner";
+
+pub fn request_realtime_poh() {
+    info!("Sending tuning request");
+    let status = UnixStream::connect(SOLANA_SYS_TUNER_PATH);
+    info!("Tuning request status {:?}", status);
+}