update sdfat library 2.0.6 to 2.1.2

[marcelv-3]

Build the source with an updated version of the sdfat library (and other libraries)
Matbe even more improved performance ?

[erichelgeson]

Thanks for the suggestion! I didnt notice any changes that would make a difference[0]. Have you tried it and did it have any improvements?

[0] https://github.com/greiman/SdFat/releases

[marcelv-3]

have tested with sdfat 2.1.2
no change in read or write speed

external LCIII
write 767 kBytes/Sec
read 1258 kBytes/Sec

could be less variation in Typical rate speed with 2.1.2 if I run Time Drive multiple times
but this requires more testing