fiq: add handler to fix compilation error

src/libboard_artiq/src/fiq.rs

@@ -0,0 +1,8 @@
+use libboard_zynq::{println, stdio};
+use libcortex_a9::interrupt_handler;
+
+interrupt_handler!(FIQ, fiq, __irq_stack0_start, __irq_stack1_start, {
+    stdio::drop_uart();
+    println!("FIQ");
+    loop {}
+});

src/libboard_artiq/src/lib.rs

@@ -1,5 +1,7 @@
 #![no_std]
+#![feature(naked_functions)]
 #![feature(never_type)]
+#![feature(asm)]
 
 extern crate core_io;
 extern crate crc;
@@ -19,6 +21,7 @@ pub mod drtioaux;
 #[cfg(has_drtio)]
 pub mod drtioaux_async;
 pub mod drtioaux_proto;
+pub mod fiq;
 #[cfg(all(feature = "target_kasli_soc", has_drtio))]
 pub mod io_expander;
 pub mod logger;