Although bash2 includes an info file, it does not run /sbin/install-info in its post-install phase to actually install a pointer to this file in the info dir file.
We can't fix it because it would cause a pre-requirement loop for new installs (bash -> install-info -> bash).
I suppose splitting the current bash RPM into bash and bash-docs (only the latter of which would depend on install-info) is a rather ugly solution, but it would be a potential one.