lima: add new findings to texture descriptor

Lower 8 bits of unknown_1_3 seems to be min_lod, rest of 4 bits + miplevels are max_lod and min_mipfilter seems to be lod bias. All are in fixed format with 4 bit integer and 4 bit fraction, lod_bias also has sign bit.

Blob also seems to do some magic with lod_bias if min filter is nearest -- it adds 0.5 to lod_bias in this case. Same story when all filters are nearest and mipmapping is enabled, but in this case it substracts 1/16 from lod_bias.

Fixes 134 dEQP tests in dEQP-GLES2.functional.texture.*

Signed-off-by: Vasily Khoruzhick anarsoul@gmail.com