boards: nxp: cleanup duplicate 'chosen' entry

 * looks like copy/paste error introduced through commit
   5df6aa8

Signed-off-by: Martin Siegumfeldt <[email protected]>

Author: mnsgs

boards/nxp/mimxrt1170_evk/mimxrt1170_evk_mimxrt1176_cm7_B.overlay

@@ -6,7 +6,6 @@
 
 / {
 	chosen {
-		zephyr,flash = &w25q512nw;
 		zephyr,flash-controller = &w25q512nw;
 		zephyr,flash = &w25q512nw;
 		zephyr,code-partition = &slot0_partition;