bash: Adding features that can not be automatically detected while cross-compiling

There are some bash features that can not be detected automatically during
configure stage while cross-compiling. This commit forces them on.

Signed-off-by: Arkady Gilinsky <arcadyg@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>