anv: Use dirty bits for dynamic state tracking

anv: Use dirty bits for dynamic state tracking

Previously, we assumed that the dirty bit was always 1 << VK_DYNAMIC_*
and this assumption is about to be false.  Extensions which define new
VK_DYNAMIC_* enums won't be nice and tightly packed which this really
requires.  Instead, add functions to don the conversions and rework the
bits a bit.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>