Rename 9160 UART to cdc_uart.

Author: Jonathan Pallant (42 Technology)

boards/nRF9160-DK/examples/blinky.rs

@@ -16,7 +16,7 @@ fn main() -> ! {
     let mut board = Board::take().unwrap();
     let mut timer = Timer::new(board.TIMER0_NS);
 
-    writeln!(board.cdc, "Hello, world!").unwrap();
+    writeln!(board.cdc_uart, "Hello, world!").unwrap();
 
     let mut led_is_on = false;
     loop {

boards/nRF9160-DK/src/lib.rs

@@ -29,7 +29,7 @@ pub struct Board {
     pub pins: Pins,
 
     /// The nRF9160-DK UART which is wired to the virtual USB CDC port
-    pub cdc: Uarte<pac::UARTE0_NS>,
+    pub cdc_uart: Uarte<pac::UARTE0_NS>,
 
     /// The LEDs on the nRF9160-DK board
     pub leds: Leds,
@@ -435,7 +435,7 @@ impl Board {
         );
 
         Board {
-            cdc: cdc_uart,
+            cdc_uart,
 
             pins: Pins {
                 P0_00: pins0.p0_00,