Create lib dir first

Author: rrooij

Makefile

@@ -17,6 +17,7 @@ testfiles := $(wildcard tests/*.plt)
 all: $(TARGET)
 
 $(TARGET): src/$(LIBNAME).o
+	mkdir -p lib/x86_64-linux
 	gcc $(LDFLAGS) -o $@ $<
 
 %.o: %.c