Handle bigger arguments to muxrpc method calls

sbotc.c

@@ -548,7 +548,7 @@ static int ps_read_header(struct boxs *bs, size_t *len, int *req_id, enum pkt_fl
 }
 
 static void muxrpc_call(struct boxs *bs, const char *method, const char *argument, enum muxrpc_type type, const char *typestr, int req_id) {
-	char req[8096];
+	char req[33792]; // 32768 max message value size + 1024 extra
 	ssize_t reqlen;
 	bool is_request = type == muxrpc_type_async;