Some arguments passed to the functions disabled with
LPM_CONF_ENABLE == 0 could trigger build warnings because they became
unused with this configuration option. Disable these functions by using
empty static inline functions instead of empty macros, so that the
function arguments are always considered by the compiler as used,
without having to #if-out code in many places.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>