#ifdef in mu_scm.h,guimb.h is superfluous.

[Alain Magloire]

Recent changes to libmu_scm/mu_scm.h, guimb/guimb.h prevent both
modules from compiling correctly on the systems that have guile
installed.

The changes were:

+#ifdef HAVE_LIBGUILE_H
#include <libguile.h>
+#endif

But HAVE_LIBGUILE_H is never defined by configure.in. The latter does

        AC_CHECK_HEADER(libguile.h, :, [GUILE_CONFIG=no])     

and then both directories are not made if GUILE_CONFIG is not set to
yes. From the other hand, when it *is* set to yes, the #ifdef/#endif
clause prevents the header from being included and any attempt of
compilation ends up in a bunch of error messages.

So, we'd better remove #ifdef/#endif.

au revoir,
Sergey