examples: Consistently use unwrap! in favor of .unwrap()

Unfortunately errors from `embedded_graphics` and `core` doesn't provide
the necessary instances currently.

examples/stm32f4/src/bin/blinky.rs

@@ -26,11 +26,11 @@ async fn main(_spawner: Spawner, p: Peripherals) {
 
     loop {
         info!("high");
-        led.set_high().unwrap();
+        unwrap!(led.set_high());
         Timer::after(Duration::from_millis(300)).await;
 
         info!("low");
-        led.set_low().unwrap();
+        unwrap!(led.set_low());
         Timer::after(Duration::from_millis(300)).await;
     }
 }

examples/stm32f4/src/bin/button.rs

@@ -28,14 +28,14 @@ fn main() -> ! {
     let mut led3 = Output::new(p.PB14, Level::High, Speed::Low);
 
     loop {
-        if button.is_high().unwrap() {
+        if unwrap!(button.is_high()) {
             info!("high");
-            led1.set_high().unwrap();
-            led3.set_low().unwrap();
+            unwrap!(led1.set_high());
+            unwrap!(led3.set_low());
         } else {
             info!("low");
-            led1.set_low().unwrap();
-            led3.set_high().unwrap();
+            unwrap!(led1.set_low());
+            unwrap!(led3.set_high());
         }
     }
 }

examples/stm32f4/src/bin/usart.rs

@@ -26,12 +26,12 @@ fn main() -> ! {
     let config = Config::default();
     let mut usart = Uart::new(p.USART3, p.PD9, p.PD8, NoDma, NoDma, config);
 
-    usart.bwrite_all(b"Hello Embassy World!\r\n").unwrap();
+    unwrap!(usart.bwrite_all(b"Hello Embassy World!\r\n"));
     info!("wrote Hello, starting echo");
 
     let mut buf = [0u8; 1];
     loop {
-        usart.read_blocking(&mut buf).unwrap();
-        usart.bwrite_all(&buf).unwrap();
+        unwrap!(usart.read_blocking(&mut buf).unwbrap());
+        unwrap!(usart.bwrite_all(&buf).unwrap());
     }
 }

examples/stm32f4/src/bin/usart_dma.rs

@@ -31,7 +31,7 @@ async fn main(_spawner: Spawner, p: Peripherals) {
         let mut s: String<128> = String::new();
         core::write!(&mut s, "Hello DMA World {}!\r\n", n).unwrap();
 
-        usart.write(s.as_bytes()).await.unwrap();
+        unwrap!(usart.write(s.as_bytes()).await);
         info!("wrote DMA");
     }
 }