[SP] Fix out of bounds array access in R_FogFactor

R_FogFactor was accessing out of array bounds due to the s texture
coordinate being NaN. This follows from using a zero-length axis to
calculate the vertex positions for a cylinder fx, which was then used in
a foggy scene.

This commit corrects problems in all of the EFX update functions, which
continued to render the EFX, even when its orientation (represented by
a 3 axes) could not be determined.