io-util: move fputs_with_newline to fileio

Follow-up for cdf6f34a2f

We already have other fputs()-like helpers in fileio rather than
io-util. While at it, switch the order of params.

src/basic/io-util.h

@@ -5,7 +5,6 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
-#include <stdio.h>
 #include <sys/types.h>
 
 #include "macro.h"
@@ -45,5 +44,3 @@ static inline bool FILE_SIZE_VALID_OR_INFINITY(uint64_t l) {
         return FILE_SIZE_VALID(l);
 
 }
-
-int fputs_with_newline(const char *s, FILE *f);