OpenGL2: Parallax corrected cubemap (cheaper trick)

(cherry picked from commit 375f6247d4faf4a2a4d14885213d1cf7516b453d)
Revert "DMA 44100Hz needs more memory for sound buffers"

This reverts commit 0e6632f464c08dcb76f26a52f33d97228e64fda1.

Cause crashes if com_soundMegs is 32.

(cherry picked from commit 0861d3c58352af59376b1a31b362b4371fd02ecd)