Updated datasheet and footprint of MIC2026 and renamed (1 letter is temperature range)

Existing datasheet link works, but it's an old Micrel datasheet, which explains part numbering:

Please notice that all -[12]BM is now -[12]YM (Pb free version).

New datasheet link: https://ww1.microchip.com/downloads/aemDocuments/documents/APID/ProductDocuments/DataSheets/MIC2026-Family-Data-Sheet-DS20006443.pdf

Previous DIP-8 package seems to be deprecated, though I still kept it in the library, linked to that old Micrel link.

New part numbers as follow:

Therefore, I renamed MIC2026-[12]BM to MIC2026-[12]xM, and updated the footprint field, which was not set.

Footprint in the new datasheet:

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