colibri-imx7: Call fdt_increase_size()

For changing the USB OTG node status from "okay" to "disabled" more
space is needed, so call fdt_increase_size() to avoid the following
error:

```
 U-Boot 2023.07-rc5-0.0.0-devel+git.580eb311 (Jun 27 2023 - 13:39:58 +0000)
 CPU:   Freescale i.MX7S rev1.2 800 MHz (running at 792 MHz)
 CPU:   Extended Commercial temperature grade (-20C to 105C) at 30C
 Reset cause: POR
 DRAM:  initcall sequence 8786eafc failed at call 8781b351 (err=-3)
 ### ERROR ### Please RESET the board ###
```

Ideally, fdt_status_disabled() should call fdt_increase_size() internally,
so that there would be no need for manually calling it in board code.

Do it manually for now to fix the regression.

Based on the code from board/CZ.NIC/turris_omnia/turris_omnia.c.

Reported-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Tested-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Toradex Colibri iMX7S