Regenerate autoconf files using current tools so proper build flags

from redhat-rpm-config are used. This resolves BZ#1548473.

fftw.spec

@@ -14,7 +14,7 @@
 
 Name:           fftw
 Version:        3.3.5
-Release:        10%{?dist}
+Release:        11%{?dist}
 Summary:        A Fast Fourier Transform library
 Group:          System Environment/Libraries
 License:        GPLv2+
@@ -22,6 +22,10 @@ URL:            http://www.fftw.org
 Source0:        http://www.fftw.org/fftw-%{version}.tar.gz
 BuildRequires:  gcc-gfortran
 
+BuildRequires:  autoconf
+BuildRequires:  automake
+BuildRequires:  libtool
+
 %global quad 0
 # Quad precision support only available with gcc >= 4.6 (Fedora >= 15)
 # and only on these arches
@@ -287,6 +291,9 @@ library.
 %setup -q
 
 %build
+# Regenerate autoconf files using current tools so proper build flags
+# from redhat-rpm-config are used
+autoreconf -vfi
 # Configure uses g77 by default, if present on system
 export F77=gfortran
 
@@ -546,6 +553,10 @@ fi
 %endif
 
 %changelog
+* Wed Apr 18 2018 Merlin Mathesius <mmathesi@redhat.com> - 3.3.5-11
+- Regenerate autoconf files using current tools so proper build flags
+  from redhat-rpm-config are used. This resolves BZ#1548473.
+
 * Wed Feb 07 2018 Fedora Release Engineering <releng@fedoraproject.org> - 3.3.5-10
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild