SAMD51 MicroMod variant name doesn't match directory name

[evenfowler]

The variant configuration for the SAMD51 MicroMod is incorrect in boards.txt which results in compilation errors. The config specifies SparkFun SAMD51 MicroMod while the variant directory is SparkFun_SAMD51_MicroMod.

In file included from /Users/$USER/Library/Arduino15/packages/SparkFun/hardware/samd/1.7.6/cores/arduino51/Arduino.h:81:0,
                 from /var/folders/wy/vc_834_n67j2fj8xqnqk0n4r0000gn/T/arduino_build_747408/sketch/Blink.ino.cpp:1:
/Users/$USER/Library/Arduino15/packages/SparkFun/hardware/samd/1.7.6/cores/arduino51/delay.h:24:21: fatal error: variant.h: No such file or directory
 #include "variant.h"
                     ^
compilation terminated.
exit status 1
Error compiling for board SparkFun SAMD51 MicroMod.

[edspark]

That is so odd, I had just fixed this locally before adding. Thanks for the pull request, I'll make sure to get it in, in the morning.