Switch to use bsp::entry to avoid deadlock on reset

src/main.rs

@@ -4,7 +4,7 @@
 #![no_std]
 #![no_main]
 
-use cortex_m_rt::entry;
+use bsp::entry;
 use defmt::*;
 use defmt_rtt as _;
 use embedded_hal::digital::v2::OutputPin;