samples: display: add support for rtk7eka6m3b00001bu shield

Enable samples/drivers/display build support for rtk7eka6m3b00001bu
display shield

Signed-off-by: The Nguyen <the.nguyen.yf@renesas.com>

Author: thenguyenyf

samples/drivers/display/sample.yaml

@@ -109,3 +109,4 @@ tests:
       - platform:frdm_mcxa156/mcxa156:SHIELD=lcd_par_s035_8080
       - platform:frdm_rw612:SHIELD=lcd_par_s035_spi
       - platform:ek_ra8d1:SHIELD=rtkmipilcdb00000be
+      - platform:ek_ra8d1:SHIELD=rtk7eka6m3b00001bu