drivers: use macro to define device structures

Replace individual device instance definitions with the macro that
expands to the equivalent change.

    F='struct device DEVICE_NAME_GET'
    git grep -l "$F" \
     | xargs sed -i -r \
       -e "s@$F"'\(([^)]*)\);@DEVICE_DECLARE(\1);@'

Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>

drivers/watchdog/wdt_sam0.c

@@ -31,7 +31,7 @@ struct wdt_sam0_dev_data {
 	bool timeout_valid;
 };
 
-static struct device DEVICE_NAME_GET(wdt_sam0);
+DEVICE_DECLARE(wdt_sam0);
 
 static struct wdt_sam0_dev_data wdt_sam0_data = { 0 };