Fix configure failure on recent macOS:
sed: RE error: illegal byte sequence
--- Mk/configure.orig 2011-02-21 13:14:35.000000000 -0600
+++ Mk/configure 2019-11-28 02:31:42.000000000 -0600
echo "# The editable source of this file is in $GENERATED.in" >> $GENERATED
sed -e "s|SRCROOTDIR=.*|SRCROOTDIR=$SRCROOTDIR|" \
$GENERATED.in >> $GENERATED
--- config/configure.orig 2012-06-04 08:01:22.000000000 -0500
+++ config/configure 2019-11-28 02:31:41.000000000 -0600
echo "# The editable source of this file is in $GENERATED.in" >> $GENERATED
sed -e "s|PREFIX=.*|PREFIX=$PREFIXDIR|" \
-e "s|SRCROOTDIR=.*|SRCROOTDIR=$SRCROOTDIR|" \
$GENERATED.in >> $GENERATED