refactor: drop string from SpuriousRateLimiterEvent erro variant

The variant was only constructed in a single place, so just make the
string that was passed there the display text for this error.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

src/vmm/src/rate_limiter/mod.rs

@@ -12,8 +12,8 @@ pub mod persist;
 #[derive(Debug, thiserror::Error, displaydoc::Display)]
 /// Describes the errors that may occur while handling rate limiter events.
 pub enum RateLimiterError {
-    /// The event handler was called spuriously: {0}
-    SpuriousRateLimiterEvent(&'static str),
+    /// Rate limiter event handler called without a present timer
+    SpuriousRateLimiterEvent,
 }
 
 // Interval at which the refill timer will run when limiter is at capacity.
@@ -470,9 +470,7 @@ impl RateLimiter {
     /// If the rate limiter is disabled or is not blocked, an error is returned.
     pub fn event_handler(&mut self) -> Result<(), RateLimiterError> {
         match self.timer_fd.read() {
-            0 => Err(RateLimiterError::SpuriousRateLimiterEvent(
-                "Rate limiter event handler called without a present timer",
-            )),
+            0 => Err(RateLimiterError::SpuriousRateLimiterEvent),
             _ => {
                 self.timer_active = false;
                 Ok(())