softpipe/aniso: move DDQ calculation to after scaling.
I've read the papers on EWA filters and it seems like the calculate DDQ = 2 * A after the scaling of A happens. This seems to make things less blurry and more like real aniso. Fixes: 2135aba8 ("softpipe: Constify variables") Reviewed-by:Timothy Arceri <tarceri@itsqueeze.com> Reviewed-by:
Roland Scheidegger <sroland@vmware.com> Part-of: <mesa/mesa!11917> (cherry picked from commit 57dcfb4e)