Add IXYS Flatpack-8 and SMD-8 for the IXYS LOC112

This MR adds two footprints for the IXYS_Flatpak-8_6.4x9.7mm_P2.54mm and IXYS_SMD-8_6.4x9.7mm_P2.54mm for the IXYS LOC112 symbols.

Datasheet: https://www.littelfuse.com/media?resourcetype=datasheets&itemid=996c6e8f-cc1b-44f6-811e-251c6e004c56&filename=littelfuse-integrated-circuits-loc112-datasheet

Symbol MR: kicad-symbols!4456 (merged)

Footprint MR: kicad-footprints!3599 (merged)

3D model MR: kicad-packages3D!999 (merged)

3D model gen MR: kicad-packages3D-generator!191 (merged)

The two two footprints were created using the Gullwing generator, because it gave the best results, although I classified the footprint as DIP. The SMD-8 is obvious. The Flatpack is similar to the ancient military Flatpack package, but with a plastic body and has the prominent DIP notch. Also, for reasons of simplicity (I did not have to create two config files), I put it together with the SMD-8 footprint into the DIP library.

IXYS_Flatpak-8_6.3x9.7mm_P2.54mm

IXYS_SMD-8_6.3x9.7mm_P2.54mm