Delete the test which compares the configuration date of libguile

Delete the test which compares the configuration date of libguile
with the configuration date of ice-9.  This test yields too many
false positives to be helpful.  For example, if you build Guile
for several architectures but have them all share a "share"
directory (which is supposed to work), then all but one
architecture's Guile will complain that the configuration dates
don't match.  Which is true, but indicates nothing wrong.
* boot-9.scm: Delete code which compares ice-9-config-stamp with
libguile-config-stamp.
* version.scm.in: Delete.
* Makefile.am (ice9_generated): Delete.
(subpkgdata_DATA): Remove ice9_generated.
(EXTRA_DIST): Remove version.scm.in.
* Makefile.in: Regenerate.