gsSPPopMatrix xml command

[Jameriquiah]

prolly very niche uses for this but could be useful for model optimization

[Jameriquiah]

before and after this addition in soh testing on a custom sword mod

using this xml displaylist

<DisplayList Version="0">
	<CallDisplayList Path="objects/object_custom_equip/gCustomMasterSwordSheathDL"/>
	<Matrix Path="objects/object_link_boy/gLinkAdultSheathedLokomoSwordMtx" Param="G_MTX_PUSH"/>
	<CallDisplayList Path="objects/object_link_boy/gLinkAdultLokomoSwordHandleDL"/>
	<PopMatrix Param="G_MTX_MODELVIEW"/>
	<EndDisplayList/>
</DisplayList>