Sprite viewer: magnified tile displayed from BG tiles instead of OBJ tiles

[rtandy]

0.8-beta1, Qt, on Debian 10.2 (buster).

In the sprite viewer, the magnified tile shown when I click on the sprite preview is taken from BG tiles instead of OBJ tiles.

Before taking the screenshots below, I clicked on the top-left part of the 2x2 sprite. The tile id (4) and palette id (0) are correct, however the tile and address displayed are for BG tile 4 (0x06000080) when it should be OBJ tile 4 (0x06010080).

[endrift]

Fixed by 158e2ef, which I accidentally typo'd the bug number in.