mtp-rs: switch to crates.io 0.15.0

Now that `mtp-rs` 0.15.0 is published, drop the local path dep and use the registry version. Same code, just a stable reference for fresh clones and CI.

Author: vdavid

Cargo.lock

@@ -161,8 +161,7 @@ mime_guess = "2"
 
 [target.'cfg(any(target_os = "macos", target_os = "linux"))'.dependencies]
 # MTP (Android device) support via pure Rust implementation
-# Path dep until mtp-rs 0.15.0 is published. Switch back to a crates.io version once released.
-mtp-rs = { path = "../../../../mtp-rs" }
+mtp-rs = "0.15.0"
 # USB hotplug detection for MTP device watcher
 nusb = "0.2.3"
 bytes = "1"