properly remove qemu static binaries from strapdir

lib/helpers

@@ -93,7 +93,7 @@ copy-root-overlay() {
 
 postbuild-clean() {
 	fn postbuild-clean
-	req=(qemu_bin strapdir release)
+	req=(strapdir release)
 	ckreq || return 1
 
 	case "$release" in
@@ -119,5 +119,8 @@ updatedb
 EOF
 
 	chroot-script -d postbuild || zerr
-	sudo rm -f $strapdir/$qemu_bin
+	sudo rm -f \
+		"$strapdir/$armel_qemu_bin" \
+		"$strapdir/$armhf_qemu_bin" \
+		"$strapdir/$arm64_qemu_bin"
 }