freedreno/a6xx: Use LDC in GL like we do for vulkan (and the blob does)
This fixes UBO loads for some of dEQP with UBO-to-constbuf optimization disabled, so this may fix apps in the wild. We emit more loads than we should because we get bad alignment information coming in, but we should be able to fix that later (and we need to for vulkan, anyway)
Edited by Emma Anholt