autogen.sh, src/Makefile.am, fix a build problem

in autogen.sh:
  libtoolize generates m4/*.m4 files
  autoheader generates config.h.in
    but only when needed

Thus a second autogen.sh invocation generated new .m4 files
  but left config.h.in untouched with old timestamp

The makefiles did recognice this situation and tried to regenerate
  config.h.in and config.h
But the subdir src/include was not the first one in src/Makefile.am
  and thus this update did occure too late,
  causing further rebuilds in the next make invocation.

Avoid this with --force arguments to the autotools,
  and put src/include into the first position.

autogen.sh

@@ -191,14 +191,14 @@ $LIBTOOLIZE --copy --force \
     || error_and_exit "$LIBTOOLIZE failed"
 
 echo "Running aclocal $ACLOCAL_FLAGS"
-aclocal $ACLOCAL_FLAGS -I m4 \
+aclocal $ACLOCAL_FLAGS --force -I m4 \
     || error_and_exit "aclocal failed"
 
 # optional feature: autoheader
 (autoheader --version) < /dev/null > /dev/null 2>&1
 if [ $? -eq 0 ]; then
   echo "Running autoheader"
-  autoheader \
+  autoheader --force \
       || error_and_exit "autoheader failed"
 fi
 
@@ -214,12 +214,12 @@ fi
 
 echo "Running autoconf"
 if [ "$ADMS" -gt 0 ]; then
-    autoconf temp-adms.ac > configure \
+    autoconf --force temp-adms.ac > configure \
         || error_and_exit "autoconf failed, with adms"
     rm -f temp-adms.ac
     chmod +x configure
 else
-    autoconf \
+    autoconf --force \
         || error_and_exit "autoconf failed"
 fi
 

src/Makefile.am

@@ -1,7 +1,7 @@
 ## Process this file with automake to produce Makefile.in
 
-SUBDIRS = misc maths frontend spicelib include/ngspice
-DIST_SUBDIRS = misc maths frontend spicelib include/ngspice xspice ciderlib unsupported
+SUBDIRS = include/ngspice misc maths frontend spicelib
+DIST_SUBDIRS = include/ngspice misc maths frontend spicelib xspice ciderlib unsupported
 
 if XSPICE_WANTED
 SUBDIRS += xspice