drivers: serial: esp32: remove unused stubs.h include

This include is only required if typeof() macro is used, which
is not the case for the serial / uart driver.

Signed-off-by: Martin Jäger <martin@libre.solar>

drivers/serial/serial_esp32_usb.c

@@ -6,7 +6,6 @@
 
 #define DT_DRV_COMPAT espressif_esp32_usb_serial
 
-#include "stubs.h"
 #include <hal/usb_serial_jtag_ll.h>
 
 #include <soc/uart_reg.h>

drivers/serial/uart_esp32.c

@@ -21,7 +21,6 @@
 #include <esp32c3/rom/gpio.h>
 #endif
 #include <soc/uart_struct.h>
-#include "stubs.h"
 #include <hal/uart_ll.h>
 #include <hal/uart_hal.h>
 #include <hal/uart_types.h>