Filter out autogenerated perl deps

Some of the documentation in %docdir (wiki/Migration*.txt) uses perl as
an interpreter, which causes rpmbuild to autogenerate deps on perl.
Filter this out as it's not needed for the main dovecot functionality.

https://bugzilla.redhat.com/show_bug.cgi?id=956194

dovecot.spec

@@ -4,7 +4,7 @@ Name: dovecot
 Epoch: 1
 Version: 2.2.1
 %global prever %{nil}
-Release: 1%{?dist}
+Release: 2%{?dist}
 #dovecot itself is MIT, a few sources are PD, pigeonhole is LGPLv2
 License: MIT and LGPLv2
 Group: System Environment/Daemons
@@ -52,6 +52,9 @@ BuildRequires: quota-devel
 # presence of AM_ICONV
 BuildRequires: gettext-devel
 
+# For the perl_default_filter macro
+BuildRequires: perl-macros
+
 # Explicit Runtime Requirements for executalbe
 Requires: openssl >= 0.9.7f-4
 
@@ -83,6 +86,9 @@ BuildRequires: curl-devel expat-devel
 BuildRequires: libcurl-devel expat-devel
 %endif
 
+# Filter out the perl dependency from the migration scripts in docdir
+%{?perl_default_filter}
+
 %global restart_flag /var/run/%{name}/%{name}-restart-after-rpm-install
 
 %description
@@ -482,6 +488,9 @@ make check
 %{_libdir}/%{name}/dict/libdriver_pgsql.so
 
 %changelog
+* Wed Apr 24 2013 Kalev Lember <kalevlember@gmail.com> - 1:2.2.1-2
+- Filter out autogenerated perl deps (#956194)
+
 * Fri Apr 19 2013 Michal Hlavinka <mhlavink@redhat.com> - 1:2.2.1-1
 - dovecot updated to 2.2.1
 - mailbox_list_index=yes was broken.