SAMD21: set the filesystem type to LFS1.
SAMD51: the type is already set to LFS2, support is now dropped for LFS1.
It has not been used and dropping it saves 10 k of flash.
Signed-off-by: robert-hh <robert@hammelrath.com>
These two boards are used for testing, so it is favorable to have them
added early.
The full test set is:
- ADAFRUIT_FEATHER_M4_EXPRESS: SAMD51 with 32kHz crystal.
- ADAFRUIT_ITSYBITSY_M0_EXPRESS: SAMD21 without crystal.
- ADAFRUIT_ITSYBITSY_M4_EXPRESS: SAMD51 without crystal.
- SEEED_XIAO: SAM21 with 32kHz crystal.