i965: Consolidate certain miptree params to flags

i965: Consolidate certain miptree params to flags

I think pretty much everyone agrees that having more than a single bool as a
function argument is bordering on a bad idea. What sucks about the current
code is in several instances it's necessary to propagate these boolean
selections down to lower layers of the code. This requires plumbing (mechanical,
but still churn) pretty much all of the miptree functions each time.  By
introducing the flags paramater, it is possible to add miptree constraints very
easily.

The use of this, as is already the case, is sometimes we have some information
at the time we create the miptree that needs to be known all the way at the
lowest levels of the create/allocation, disable_aux_buffers is currently one
such example. There will be another example coming up in a few patches.

v2:
Tab fix. (Ben)
Long line fixes (Topi)
Use anonymous enum instead of #define for layout flags (Chad)
Use 'X != 0' instead of !!X (everyone except Chad)

v3:
Some non-trivial conflict resolution on top of Anuj's patches.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Cc: "Pohjolainen, Topi" <topi.pohjolainen@intel.com>
Reviewed-by: Chad Versace <chad.versace@intel.com>
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>