colibri_imx7: remove legancy UART platform data

We now use device tree to provide SoC data to the UART driver, there
is no need for the legancy UART platform data.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>

board/toradex/colibri_imx7/colibri_imx7.c

@@ -368,13 +368,3 @@ int board_ehci_hcd_init(int port)
 	return 0;
 }
 #endif
-
-static struct mxc_serial_platdata mxc_serial_plat = {
-	.reg = (struct mxc_uart *)UART1_IPS_BASE_ADDR,
-	.use_dte = true,
-};
-
-U_BOOT_DEVICE(mxc_serial) = {
-	.name = "serial_mxc",
-	.platdata = &mxc_serial_plat,
-};