luajit: needs for 32bit archictectures a 32bit host gcc

For 32 bit archictectures the luajit package needs a host compiler
able to generate 32 bit code using the "-m32" option so check if that
option is supported.

Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Cc: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: François Perrad <francois.perrad@gadz.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>