intel/compiler: Run extra fp64 lowering pass on devices that don't support int64.

In some cases nir_lower_int64 will emit fp64 operations which aren't
natively supported on any Intel hardware (e.g. ftrunc, frem).  An
extra pass of nir_opt_algebraic (for frem) and nir_lower_doubles is
required in order to take care of them.  This fixes several int64
test-cases on MTL hardware.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Mykhailo Skorokhodov <mykhailo.skorokhodov@globallogic.com>
Part-of: <!19390>