berkeleydb: add option for tools install

Add an option to install (or not) the berkeleydb binary tools.
The default is no since most of the time/application just need the
library and it helps save some space in the target.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>