Without the `= 0` declaration, compiling with RTTI enabled fails.
See http://stackoverflow.com/a/307427/1880101 for an explanation.

See https://github.com/pasko-zh/brzo_i2c for more info about the
library. It is very fast and can run the OLED at 120fps even in 80Mhz
mode.

Signed-off-by: CaptainStouf <stouf@hardware-libre.org>