Stop building vers.c in include/ and only build the needed osreldate.h.

Because of how osreldate.h was being built with newvers.sh, which always
spat out a vers.c dependent on SVN or git, the meta mode build was
considering osreldate.h to depend on the current git or SVN index.  This
would lead to entire tree rebuilds when modifying git's index.  There's
no reason to be generating vers.c here so just skip it.

While here, in mk-osreldate.sh rename PARAM_H to proper PARAMFILE (which
newvers.sh already has a default for) and remove unneeded export.

Sponsored by:	EMC / Isilon Storage Division

include/Makefile

@@ -5,7 +5,7 @@
 
 .include <src.opts.mk>
 
-CLEANFILES= osreldate.h version vers.c
+CLEANFILES= osreldate.h version
 SUBDIR= arpa protocols rpcsvc rpc xlocale
 SUBDIR_PARALLEL=
 INCS=	a.out.h ar.h assert.h bitstring.h complex.h cpio.h _ctype.h ctype.h \
@@ -104,12 +104,8 @@ NEWVERS_SH=		${SYSDIR}/conf/newvers.sh
 PARAM_H=		${SYSDIR}/sys/param.h
 MK_OSRELDATE_SH=	${.CURDIR}/mk-osreldate.sh
 
-osreldate.h vers.c: ${NEWVERS_SH} ${PARAM_H} ${MK_OSRELDATE_SH}
-	env ECHO="${ECHO}" \
-	    MAKE="${MAKE}" \
-	    NEWVERS_SH=${NEWVERS_SH} \
-	    PARAM_H=${PARAM_H} \
-	    SYSDIR=${SYSDIR} \
+osreldate.h: ${NEWVERS_SH} ${PARAM_H} ${MK_OSRELDATE_SH}
+	env NEWVERS_SH=${NEWVERS_SH} PARAMFILE=${PARAM_H} SYSDIR=${SYSDIR} \
 	    sh ${MK_OSRELDATE_SH}
 
 .for i in ${LHDRS}

include/mk-osreldate.sh

@@ -35,8 +35,8 @@ trap "rm -f $tmpfile" EXIT
 
 ${ECHO} creating osreldate.h from newvers.sh
 
-export PARAMFILE="${PARAM_H:=$CURDIR/../sys/sys/param.h}"
 set +e
+VARS_ONLY=1
 . "${NEWVERS_SH:=$CURDIR/../sys/conf/newvers.sh}" || exit 1
 set -e
 cat > $tmpfile <<EOF

sys/conf/newvers.sh

@@ -84,6 +84,12 @@ fi
 COPYRIGHT="$COPYRIGHT
 "
 
+# VARS_ONLY means no files should be generated, this is just being
+# included.
+if [ -n "$VARS_ONLY" ]; then
+	return 0
+fi
+
 LC_ALL=C; export LC_ALL
 if [ ! -r version ]
 then