Fix compilation of FYBA with GCC 6 (#8273)

var/spack/repos/builtin/packages/fyba/gcc-6.patch

@@ -0,0 +1,18 @@
+diff -Nuar a/src/FYBA/FYLU.cpp b/src/FYBA/FYLU.cpp
+--- a/src/FYBA/FYLU.cpp	2014-09-22 00:36:49.000000000 -0500
++++ b/src/FYBA/FYLU.cpp	2018-05-24 15:35:43.584181379 -0500
+@@ -4,12 +4,12 @@
+ /*  Innhold: Rutiner for utvalg                                             */
+ /* ======================================================================== */
+ 
+-#include "stdafx.h"
+-
+ #include <ctype.h>
+ #include <math.h>
+ #include <locale>
+ 
++#include "stdafx.h"
++
+ using namespace std;
+ 
+ #define U_PARA_LEN    128     /* Max lengde av parameterstreng */

var/spack/repos/builtin/packages/fyba/package.py

@@ -43,6 +43,10 @@ class Fyba(AutotoolsPackage):
     depends_on('libtool',  type='build')
     depends_on('m4',       type='build')
 
+    # error: macro "min" passed 3 arguments, but takes just 2
+    # https://github.com/kartverket/fyba/issues/21
+    patch('gcc-6.patch')
+
     # fatal error: 'sys/vfs.h' file not found
     # https://github.com/kartverket/fyba/issues/12
     patch('vfs-mount-darwin.patch', when='platform=darwin')