svga: fix PIPE_CAP_MAX_TEXTURE_BUFFER_SIZE value
This query is supposed to return the max texture buffer size/width in texels, not size in bytes. Divide by 16 (the largest format size) to return texels. Fixes Piglit arb_texture_buffer_object-max-size test. Cc: mesa-stable@lists.freedesktop.org Reviewed-by :Charmaine Lee <charmainel@vmware.com>