i965: Use miptree to decide format on multi-plane images for gen < 7
This wasn't handled correctly for multi-plane images on gen < 7 in 727a9b24. Reported-by:Mark Janes <mark.a.janes@intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96674 Signed-off-by:
Jordan Justen <jordan.l.justen@intel.com> Cc: "12.0" <mesa-stable@lists.freedesktop.org> Reviewed-by:
Jason Ekstrand <jason@jlekstrand.net> (cherry picked from commit 367cf3a2)