mesa: fix texture3D mipmap generation for UNSIGNED_BYTE_3_3_2 and 4_4
mesa: fix texture3D mipmap generation for UNSIGNED_BYTE_3_3_2 and 4_4

Oops, I copy-pasted a typo from 3_3_2.

The 3_3_2 part is a candidate for 7.9 and 7.10.
The 4_4 part isn't, because AL44 is in neither branches.

benaadams/glsl-optimizer,bkaradzic/glsl-optimizer,adobe/glsl2agal,jbarczak/glsl-optimizer,dellis1972/glsl-optimizer,mapbox/glsl-optimizer,mapbox/glsl-optimizer,djreep81/glsl-optimizer,jbarczak/glsl-optimizer,djreep81/glsl-optimizer,zz85/glsl-optimizer,benaadams/glsl-optimizer,jbarczak/glsl-optimizer,zz85/glsl-optimizer,tokyovigilante/glsl-optimizer,mcanthony/glsl-optimizer,mcanthony/glsl-optimizer,bkaradzic/glsl-optimizer,tokyovigilante/glsl-optimizer,zeux/glsl-optimizer,bkaradzic/glsl-optimizer,KTXSoftware/glsl2agal,benaadams/glsl-optimizer,mapbox/glsl-optimizer,djreep81/glsl-optimizer,zeux/glsl-optimizer,metora/MesaGLSLCompiler,KTXSoftware/glsl2agal,jbarczak/glsl-optimizer,tokyovigilante/glsl-optimizer,zeux/glsl-optimizer,tokyovigilante/glsl-optimizer,KTXSoftware/glsl2agal,wolf96/glsl-optimizer,metora/MesaGLSLCompiler,mcanthony/glsl-optimizer,zz85/glsl-optimizer,mapbox/glsl-optimizer,benaadams/glsl-optimizer,wolf96/glsl-optimizer,djreep81/glsl-optimizer,bkaradzic/glsl-optimizer,wolf96/glsl-optimizer,adobe/glsl2agal,adobe/glsl2agal,dellis1972/glsl-optimizer,benaadams/glsl-optimizer,mcanthony/glsl-optimizer,mapbox/glsl-optimizer,dellis1972/glsl-optimizer,benaadams/glsl-optimizer,wolf96/glsl-optimizer,wolf96/glsl-optimizer,tokyovigilante/glsl-optimizer,adobe/glsl2agal,jbarczak/glsl-optimizer,zeux/glsl-optimizer,zeux/glsl-optimizer,zz85/glsl-optimizer,metora/MesaGLSLCompiler,mcanthony/glsl-optimizer,zz85/glsl-optimizer,KTXSoftware/glsl2agal,KTXSoftware/glsl2agal,adobe/glsl2agal,djreep81/glsl-optimizer,dellis1972/glsl-optimizer,zz85/glsl-optimizer,bkaradzic/glsl-optimizer,dellis1972/glsl-optimizer