cmdline: Print available protocols when --version is run.

src/ls.h

@@ -20,6 +20,7 @@
 #define MPD_LS_H
 
 #include <stdbool.h>
+#include <stdio.h>
 
 struct client;
 
@@ -36,4 +37,9 @@ bool uri_supported_scheme(const char *url);
  */
 void print_supported_uri_schemes(struct client *client);
 
+/**
+ * Send a list of supported URI schemes to a file pointer.
+ */
+void print_supported_uri_schemes_to_fp(FILE *fp);
+
 #endif