boards: xiao_esp32s3: Fix connector definition

Previously the seed connector was defined incorrectly and as such D6 and D7
weren't usable as i.e. inputs. Zephyr distinguishes GPIO pins in blocks of
32, a distinction the ESP32 reference manual doesn't do. As such one needs
to write `&gpio1 11` in order to access `GPIO43`.

Signed-off-by: Sophie 'Tyalie' Friedrich <dev@flowerpot.me>
(cherry picked from commit 70cb9349)