main.h includes statements which (re)define preprocessor variables which
influence the compiled code. This makes it necessary to include it in all
files. For example, it redefines pr_fmt used to the module as prefix for
each pr_* message.
Reported-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>