The additional spinners in the splitscreen kart selection screen don't highlight the navigation arrows correctly

[Alayan-stk-2]

For their spinners, themes keep the side arrows of spinners grey unless the arrow is active. When active, it receives a highlight color, which is particularly useful when navigating the menu with the keyboard or a gamepad.

In the splitscreen kart selection screen:

• The spinners to pick the player name are fully colored, including the arrows
• Because of the way navigation works in this screen, an arrow is not properly picked as active when first navigating by keyboard/gamepad to the spinner, requiring an additional key/button press.
• More importantly, only the first player benefits from arrows being highlighted as active. Subsequent players don't receive any visual clue as to which arrow is active.