Updated enum docs for MultiPath

Author: schjonhaug

wallet/src/descriptor/error.rs

@@ -21,7 +21,7 @@ pub enum Error {
     InvalidDescriptorChecksum,
     /// The descriptor contains hardened derivation steps on public extended keys
     HardenedDerivationXpub,
-    /// The descriptor contains multipath keys
+    /// The descriptor contains multipath keys with an invalid number of paths (must have exactly 2 paths for receive and change)
     MultiPath,
     /// Error thrown while working with [`keys`](crate::keys)
     Key(crate::keys::KeyError),