Use nearest scaling for DRAW_ALPHA_BLEND since this is what win32 needs
Use nearest scaling for DRAW_ALPHA_BLEND since this is what win32 needs

DrvAlphaBlend is the only current user of DRAW_ALPHA_BLEND, and its
defined to do nearest (COLORONCOLOR) scaling, not bilinear.

fgouget/spice-common,Fantu/spice-common,SPICE/spice-common,fgouget/spice-common,elmarco/spice-common,Fantu/spice-common,fgouget/spice-common,freedesktop-unofficial-mirror/spice__spice-common,SPICE/spice-common,fgouget/spice-common,freedesktop-unofficial-mirror/spice__spice-common,elmarco/spice-common,Fantu/spice-common,Fantu/spice-common,elmarco/spice-common,freedesktop-unofficial-mirror/spice__spice-common,elmarco/spice-common,SPICE/spice-common,freedesktop-unofficial-mirror/spice__spice-common