d3dx9: D3DXCreateMeshFVF

[Luis Buquets]

Instead of implementing D3DXCreateMeshFVF, wouldn't it be better to 
implement D3DXCreateMesh and call the latter from D3DXCreateMeshFVF by 
previously using D3DXDeclaratorFromFVF?

D3DXCreateMeshFVF would be pretty straight then:
1. get the const LPD3DVERTEXELEMENT9 *pDeclaration from the supplied FVF
2. call D3DXCreateMesh

BTW, D3DXGetFVFVertexSize could then also be forwarded to 
D3DXGetDeclVertexSize and the code simplified.