115200 is a much more sane "default" than 38400.
Instead of a mix of 38400 and 115200, just use 115200 in all places.
There's no reason for modern 32bit cpus to be using such old slow
baudrates.
Tested on f1, f4, l1. Replaced some old f1 code that predated some
library support code for this.
Using the latest (as of today) gcc-arm-embedded toolchain caused two build
failures similar to:
error: unknown type name 'cookie_io_functions_t'
These custom IO functions are now protected by a define, so define _GNU_SOURCE
which enables all such areas. This is a libc issue.
Signed-off-by: Trevor Woerner <twoerner@gmail.com>