targets: use the non-inline sw helpers

Previously (with the inline ones) things were embedded into the
pipe-loader, which means that we cannot control/select what we want in
each target.

That also meant that at runtime we ended up with the empty
sw_screen_create() as the GALLIUM_SOFTPIPE/LLVMPIPE were not set.

v2: Cover all the targets, not just dri.

Cc: "11.1" <mesa-stable@lists.freedesktop.org>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: Edward O'Callaghan <edward.ocallaghan@koparo.com>
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Tested-by: Oded Gabbay <oded.gabbay@gmail.com>
Tested-by: Nick Sarnie <commendsarnex@gmail.com>
7 files changed