common/hooks: remove config variable enable vcdiff generation.

common/hooks/post-pkg/01-xdelta_repolist.sh

@@ -2,7 +2,7 @@
 
 hook() {
 	set -x
-	[ -z "$XBPS_GENERATE_VCDIFF" ] && return 0;
+	type -P xdelta3 > /dev/null || return 0;
 
 	find $XBPS_REPOSITORY -name '*.genVcdiff' | xargs -r sha256sum | \
 		while read chk oldfile; do

common/hooks/pre-pkg/01-xdelta_repolist.sh

@@ -1,7 +1,7 @@
 # this hook marks files which are about to change for generating vcdiffs
 
 hook() {
-	[ -z "$XBPS_GENERATE_VCDIFF" ] && return 0;
+	type -P xdelta3 > /dev/null || return 0;
 
 	# create links to preserve old versions of repodata
 	find $XBPS_REPOSITORY -name '*-repodata' | \

xbps-src

@@ -469,8 +469,7 @@ export XBPS_SHUTILSDIR XBPS_CROSSPFDIR XBPS_TRIGGERSDIR \
     XBPS_CCACHE XBPS_DISTCC XBPS_DISTCC_HOSTS XBPS_SKIP_DEPS \
     XBPS_SKIP_REMOTEREPOS XBPS_CROSS_BUILD XBPS_PKG_OPTIONS \
     XBPS_CONFIG_FILE XBPS_KEEP_ALL XBPS_HOSTDIR XBPS_MASTERDIR \
-    XBPS_SRC_VERSION XBPS_DESTDIR FAKEROOT_CMD CHROOT_CMD XBPS_MACHINE \
-    XBPS_GENERATE_VCDIFF
+    XBPS_SRC_VERSION XBPS_DESTDIR FAKEROOT_CMD CHROOT_CMD XBPS_MACHINE
 
 for i in REPOSITORY DESTDIR BUILDDIR SRCDISTDIR; do
     eval val="\$XBPS_$i"