tools/libtool: remove parallel building

There is only one subdirectory for libtool that actually compiles,
so enabling parallel building has no significant beneficial effects.

Signed-off-by: Michael Pratt <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/16522
Signed-off-by: Robert Marko <[email protected]>

tools/libtool/Makefile

@@ -14,8 +14,6 @@ PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=@GNU/$(PKG_NAME)
 PKG_HASH:=da8ebb2ce4dcf46b90098daf962cffa68f4b4f62ea60f798d0ef12929ede6adf
 
-HOST_BUILD_PARALLEL:=1
-
 include $(INCLUDE_DIR)/host-build.mk
 
 export GNULIB_SRCDIR:=$(HOST_GNULIB_SRCDIR)