Build fixing for FreeBSD. GNU make is installed as gmake, so make a MAKE
variable (defaults to "make") and use that. Use the MKDEP and MKDEP_OPTIONS
more. Our shell isn't bash, so change the instances of ">& /dev/null" to a more
compatible "> /dev/null 2>&1".
Use tcc and the emitted C code from s_fragprog_to_c.c to dynamically compile
and execute fragment programs. Very limited and experimental, but works
well enough to run arbfplight.c.
http://fabrice.bellard.free.fr/tcc/
Compile with 'make linux-tcc', being sure to make clean first.