build: bootstrap fixes.

* build-aux/config.sh.in (bootstrap): Set up for substitution.
* configure.sh (bootstrap): Substitute.
* build-aux/install.sh.in (_v): Robustify check for V.
(__exclude_go, __exclude_scm): Initialize.

build-aux/config.sh.in

@@ -52,7 +52,7 @@ arch="@arch@"
 build="@build@"
 host="@host@"
 
-bootstrap=${bootstrap-}
+bootstrap=${bootstrap-@bootstrap@}
 compiler=${compiler-@compiler@}
 courageous=${courageous-@courageous@}
 mes_system=@mes_system@

build-aux/install.sh.in

@@ -27,10 +27,12 @@ _v=
 if test "$V" = 2; then
     set -x
 fi
+if test -n "$V"; then
     if test "$V" -gt 0; then
         v=v
         _v=-v
     fi
+fi
 
 set -u
 
@@ -77,6 +79,8 @@ else
     cp $_v ChangeLog ${DESTDIR}${docdir}
 fi
 
+__exclude_go=
+__exclude_scm=
 if test -f module/mescc.go; then
     __exclude_go=--exclude='*.go'
     __exclude_scm=--exclude='*.scm'

configure.sh

@@ -110,6 +110,7 @@ subst () {
     -e s,"@PACKAGE_NAME@,$PACKAGE_NAME,"\
     -e s,"@PACKAGE_BUGREPORT@,$PACKAGE_BUGREPORT,"\
     -e s,"@VERSION@,$VERSION,"\
+    -e s,"@bootstrap@,yes,"\
     -e s,"@build@,$build,"\
     -e s,"@host@,$host,"\
     -e s,"@compiler@,$compiler,"\