Dynamic shadows artifacts

[Deathrey (DeathreyCG)]

@Kalle-H

Just found another problem that contributes this problem. When Gather4 isn’t used code is calling function. FetchRowOfThree() this always offset towards positive x coords. Calling code always use positive offsets. This Shifts shadows 1-2 texels(on both axis) depending if pcf2 or 3 is used.

This is is true for mobile platforms. The kernel is missing 1 texel of offset, when MOBILE_CSM_QUALITY == 2.

FetchRowOfThree() is not used anywhere else.