...which is no longer used.  Also, use the detected BASH value in Makefile.in
instead of re-detecting there.  (Though setting SHELL in Makefile.in is likely
bogus anyway, cf. "this is overridden by solenv/gbuild/gubild.mk [...] i don't
know what needs the 'SHELL=bash' in top-level makefile",
<http://lists.freedesktop.org/archives/libreoffice/2013-March/048552.html> "Re:
need help with shell / configure.")

Change-Id: I09c8b5eb9fb1244321d1fb998bb78e458e8ebf37