time: replace dyn clock/alarm with a global Driver trait

examples/stm32f4/src/bin/blinky.rs

@@ -6,7 +6,6 @@
 
 #[path = "../example_common.rs"]
 mod example_common;
-use defmt::panic;
 use embassy::executor::Spawner;
 use embassy::time::{Duration, Timer};
 use embassy_stm32::dbgmcu::Dbgmcu;

examples/stm32f4/src/bin/button_exti.rs

@@ -6,7 +6,6 @@
 
 #[path = "../example_common.rs"]
 mod example_common;
-use defmt::panic;
 use embassy::executor::Spawner;
 use embassy_stm32::dbgmcu::Dbgmcu;
 use embassy_stm32::exti::ExtiInput;

examples/stm32f4/src/bin/hello.rs

@@ -4,7 +4,7 @@
 #![feature(type_alias_impl_trait)]
 #![allow(incomplete_features)]
 
-use defmt::{info, panic};
+use defmt::info;
 use embassy::executor::Spawner;
 use embassy::time::{Duration, Timer};
 use embassy_stm32::time::Hertz;

examples/stm32f4/src/bin/spi_dma.rs

@@ -8,7 +8,6 @@
 mod example_common;
 use core::fmt::Write;
 use core::str::from_utf8;
-use defmt::panic;
 use embassy::executor::Spawner;
 use embassy_stm32::dbgmcu::Dbgmcu;
 use embassy_stm32::spi::{Config, Spi};

examples/stm32f4/src/bin/usart_dma.rs

@@ -7,7 +7,6 @@
 #[path = "../example_common.rs"]
 mod example_common;
 use core::fmt::Write;
-use defmt::panic;
 use embassy::executor::Spawner;
 use embassy_stm32::dbgmcu::Dbgmcu;
 use embassy_stm32::dma::NoDma;