Add support for USB flash
    Converted note content to a sub section on install bossac
    This closes: OSTC/planning/hw-enablement#30

Signed-off-by: Gururaj Shetty <gururaj.shetty@huawei.com>

Davide Ricci authored 3 years ago and Stefan Schmidt committed 3 years ago

Signed-off-by: Davide Ricci <davide.ricci@huawei.com>

Details of the arduino-nano-33-ble.rst
How to flash
This closes OSTC/planning/hw-enablement#29

Signed-off-by: shettygururaj <gururaj.shetty@huawei.com>