gallium: use put image shm2 path (v2)

This fixes the drisw paths to use the new shm2 interface, so that
we don't trigger the X server overflow checks when the x offset is non-zero.

This just hides the versioning in drisw, and either passes the src_x
or adds the offset fixup for the fallback path.

Cc: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Adam Jackson <ajax@redhat.com>
(cherry picked from commit 1f6b92b4)