Revert "atmel-samd: Tweak mass storage code to finish read sooner."
Revert "atmel-samd: Tweak mass storage code to finish read sooner."

This reverts commit 182a946b0ef12f6f031e846af788cdeb2eecd3a6.

adafruit/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/circuitpython,adafruit/micropython,adafruit/circuitpython,adafruit/micropython,adafruit/micropython