enable flockfile and friends if threads are not enabled

libc/stdio/Makefile

@@ -58,9 +58,7 @@ CSRC += fopencookie.c fmemopen.c open_memstream.c
 endif
 
 # pthread functions
-ifeq ($(strip $(UCLIBC_HAS_THREADS)),y)
 CSRC += flockfile.c ftrylockfile.c funlockfile.c
-endif
 
 # Functions with unlocked versions
 CUSRC = clearerr.c feof.c ferror.c fflush.c fgetc.c fgets.c fileno.c \