Add TERMUX_SUBPKG_REPLACES to make it possible to for subpackages to replace packages.

build-package.sh

@@ -1043,6 +1043,7 @@ termux_step_massage() {
 		local SUB_PKG_DIR=$TERMUX_TOPDIR/$TERMUX_PKG_NAME/subpackages/$SUB_PKG_NAME
 		local TERMUX_SUBPKG_DEPENDS=""
 		local TERMUX_SUBPKG_CONFLICTS=""
+		local TERMUX_SUBPKG_REPLACES=""
 		local TERMUX_SUBPKG_CONFFILES=""
 		local SUB_PKG_MASSAGE_DIR=$SUB_PKG_DIR/massage/$TERMUX_PREFIX
 		local SUB_PKG_PACKAGE_DIR=$SUB_PKG_DIR/package
@@ -1083,6 +1084,7 @@ termux_step_massage() {
 		HERE
 		test ! -z "$TERMUX_SUBPKG_DEPENDS" && echo "Depends: $TERMUX_SUBPKG_DEPENDS" >> control
 		test ! -z "$TERMUX_SUBPKG_CONFLICTS" && echo "Conflicts: $TERMUX_SUBPKG_CONFLICTS" >> control
+		test ! -z "$TERMUX_SUBPKG_REPLACES" && echo "Replaces: $TERMUX_SUBPKG_REPLACES" >> control
 		tar -cJf "$SUB_PKG_PACKAGE_DIR/control.tar.xz" .
 
 		for f in $TERMUX_SUBPKG_CONFFILES; do echo "$TERMUX_PREFIX/$f" >> conffiles; done