B button replacement icons don't display right for SMS

[MapMappening]

Game Name?

Super Mario Sunshine

Game ID?

GMSE01

Input device ID?

SDL/0/Controller (Gamepad F310)

Dolphin version?

2506a

Operating System?

Windows 10

Describe the bug.

The texture has some not fully transparent areas for icons of this controller, namely the area of the icon and the top and bottoms. This causes almost the entire button to light up as it strobes when it shouldn't.

Expected behavior.

Only the letter should be lighting up, so that it 'blooms' out when the apex of the strobe is reached and be transparent vice-versa.