minor, use auto keyword as storage for closures in rand.c

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, use auto keyword as storage for closures in rbm.c

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, link rbm(1) and rand-test helper with -lm explicitly ...

This is necessary to support the gcc compiler which (for whatever reasons)
cannot determine whether or not -lm is needed.

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'bld/gcc'

* bld/gcc:
  chore, link rbm(1) and rand-test helper with -lm explicitly ...
  minor, use auto keyword as storage for closures in rbm.c
  minor, use auto keyword as storage for closures in rand.c