boards: shields: adafruit_2_8_tft_touch_v2: fix RW612 board overlay

RW612 board overlay should remove the MIPI DBI nodes defined at the
board and at the shield level, because the LCDIC peripheral on this SOC
can support the MIPI DBI protocol directly without the emulated Zephyr
driver.

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>