AVX512 PacketMath add quarter type

Submitted by neu..@..eck.de

Assigned to Nobody

Link to original bugzilla bug (#1714)
Version: 3.4 (development)
Platform: x86 - AVX512

Description

AVX512 could define a quarter type since there are three usable types (ignoring suffixes):

__mm512

__mm256

__mm128

so dealing with a vector of ten double elements could be done by

one m512 and one m128 instruction/packet.

Depends on

#692