Remove scm_putc_unlocked.

* libguile/ports.h (scm_putc_unlocked): Remove.
* libguile/ports.c (scm_putc): Replace implementation with
  scm_putc_unlocked's implementation.
  (scm_port_print): Use scm_putc.
* libguile/arbiters.c:
* libguile/arrays.c:
* libguile/bitvectors.c:
* libguile/bytevectors.c:
* libguile/continuations.c:
* libguile/dynl.c:
* libguile/eval.c:
* libguile/filesys.c:
* libguile/fluids.c:
* libguile/foreign.c:
* libguile/fports.c:
* libguile/frames.c:
* libguile/hashtab.c:
* libguile/hooks.c:
* libguile/macros.c:
* libguile/mallocs.c:
* libguile/print.c:
* libguile/programs.c:
* libguile/promises.c:
* libguile/r6rs-ports.c:
* libguile/smob.c:
* libguile/srcprop.c:
* libguile/struct.c:
* libguile/variable.c:
* libguile/weak-set.c:
* libguile/weak-table.c: Use scm_putc instead of scm_putc_unlocked.

libguile/frames.c

@@ -49,7 +49,7 @@ scm_i_frame_print (SCM frame, SCM port, scm_print_state *pstate)
 
       if (scm_is_true (name))
         {
-          scm_putc_unlocked (' ', port);
+          scm_putc (' ', port);
           scm_write (name, port);
         }
     }