tools/flex: disable building shared libfl.so

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

Backport of r42308

git-svn-id: svn://svn.openwrt.org/openwrt/branches/barrier_breaker@42310 3c298f89-4303-0410-b956-a3cf2f4a3e73

tools/flex/Makefile

@@ -18,6 +18,7 @@ HOST_BUILD_PARALLEL:=1
 
 include $(INCLUDE_DIR)/host-build.mk
 
+HOST_CONFIGURE_ARGS += --disable-shared
 HOST_LDFLAGS += $(HOST_STATIC_LINKING)
 
 define Host/Clean