feat: 初步支持 USB 网卡桥接；删除 OTG 端点预算管理

src/otg/configfs.rs

@@ -75,11 +75,6 @@ fn collect_dir_names(path: &Path, devices: &mut Vec<String>) {
     }
 }
 
-pub fn is_low_endpoint_udc(name: &str) -> bool {
-    let name = name.to_ascii_lowercase();
-    name.contains("musb") || name.contains("musb-hdrc")
-}
-
 /// Sysfs/configfs: one write syscall with final buffer (incl. newline when needed).
 pub fn write_file(path: &Path, content: &str) -> Result<()> {
     let mut file = OpenOptions::new()