batman-adv: Fix function names on new line starting with '*'

Some really long function names in batman-adv require a newline between
return type and the function name. This has lead to some lines starting
with *batadv_...

This * belongs to the return type and thus should be on the same line as
the return type.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>