opengles Translator: fix uncompress palleted A1 textures

There was a bug in uncompress of GL_PALETTE4_RGB5_A1_OES and
GL_PALETTE8_RGB5_A1_OES texture formats.
They were considered RGB (not RGBA) for some reason.
This also fixed the pink sky in Wave Blazer Lite

Change-Id: I8c047d624d9bf09e2a0de7f7340d676cfe5e76c9
1 file changed