Fix compilation error

src/mc/favicon.rs

@@ -1,7 +1,7 @@
 use crate::proto::client::ClientInfo;
 
 /// Protocol version since when favicons are supported.
-const FAVICON_PROTOCOL_VERSION: i32 = 4;
+const FAVICON_PROTOCOL_VERSION: u32 = 4;
 
 /// Get default server status favicon.
 pub fn default_favicon() -> String {
@@ -20,7 +20,7 @@ pub fn encode_favicon(data: &[u8]) -> String {
 /// Defaults to `true` if unsure.
 pub fn supports_favicon(client_info: &ClientInfo) -> bool {
     client_info
-        .protocol_version
+        .protocol
         .map(|p| p >= FAVICON_PROTOCOL_VERSION)
         .unwrap_or(true)
 }