Move %configure and associated steps to %build

%configure and friends invoke code that is part of the package
and should be in %build.

If https://src.fedoraproject.org/rpms/redhat-rpm-config/pull-request/172
is merged, %configure would start throwing an error. This change
is proactively to avoid a later build failure. No rebuild will
be done.

dovecot-fts-xapian.spec

@@ -25,11 +25,11 @@ users.
 
 %prep
 %autosetup -n fts-xapian-%{version}
+
+%build
 autoreconf -vi
 %configure --enable-static=no --with-dovecot=%{_libdir}/dovecot
 
-
-%build
 %make_build
 
 %install