Incorrect color scaling values in sprites, tiles and maps viewer

[Prof9]

Using latest development build downloaded from mgba.io.

Color component values are scaled incorrectly in the sprites, tiles and maps viewers. For example, a pure white pixel (31,31,31) is shown as having Red: 0xf8 (248), Green: 0xf8 (248) and Blue: 0xf8 (248) components. The pixels themselves are displayed correctly, just the textual representation is incorrect.

In the palette viewer, the colors are correctly scaled, e.g. a (31,31,31) pixel is correctly shown as having hex value #ffffff.