picolibc: Add stdout buffering [v2]
picolibc: Add stdout buffering [v2]

Add buffering so that USB back-ends get some batching for stdout

Signed-off-by: Keith Packard <keithp@keithp.com>

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v2:
	Replace tabs with spaces.

OTAkeys/RIOT,jasonatran/RIOT,authmillenon/RIOT,ant9000/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,miri64/RIOT,kYc0o/RIOT,OTAkeys/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,OlegHahm/RIOT,kaspar030/RIOT,authmillenon/RIOT,OlegHahm/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,jasonatran/RIOT,ant9000/RIOT,kYc0o/RIOT,OlegHahm/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,miri64/RIOT,authmillenon/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,kaspar030/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,miri64/RIOT,ant9000/RIOT,OTAkeys/RIOT,kaspar030/RIOT,authmillenon/RIOT,jasonatran/RIOT,authmillenon/RIOT,miri64/RIOT,RIOT-OS/RIOT,ant9000/RIOT,miri64/RIOT,jasonatran/RIOT,kYc0o/RIOT,ant9000/RIOT