Adjust wording of two fall-through comments.

In two places in glibc, -Wextra produces implicit-fallthrough warnings
where there are comments about the fall-through but their wording
doesn't match one of the forms expected by the default
implicit-fallthrough level.  This patch adjusts those two places to
have a comment in a form that is accepted, so avoiding the warning
(this seems preferable to only being able to use a looser level of the
warning that allows any comment at all as evidence of deliberate
fall-through).

Tested for x86_64.

	* iconvdata/cns11643.h (ucs4_to_cns11643): Adjust fall-through
	comment wording.
	* nis/nis_call.c (__do_niscall3): Likewise.

ChangeLog

@@ -1,5 +1,9 @@
 2019-02-13  Joseph Myers  <joseph@codesourcery.com>
 
+	* iconvdata/cns11643.h (ucs4_to_cns11643): Adjust fall-through
+	comment wording.
+	* nis/nis_call.c (__do_niscall3): Likewise.
+
 	* catgets/gencat.c (normalize_line): Use braces around empty
 	'else' body.
 	* include/stap-probe.h [!USE_STAP_PROBE && !__ASSEMBLER__]

iconvdata/cns11643.h

@@ -220,7 +220,8 @@ ucs4_to_cns11643 (uint32_t wch, unsigned char *s, size_t avail)
       cp = __cns11643l1_from_ucs4_tab12[ch - 0x4e00];
       if (cp[0] != '\0')
 	break;
-      /* FALLTHROUGH.  Let's try the other planes.  */
+      /* Let's try the other planes.  */
+      /* Fall through.  */
     case 0x3400 ... 0x4dff:
     case 0x9f9d ... 0x9fa5:
       /* Let's try the other planes.  */

nis/nis_call.c

@@ -325,6 +325,7 @@ __do_niscall3 (dir_binding *dbp, u_long prog, xdrproc_t xargs, caddr_t req,
 		}
 	      /* Yes, the missing break is correct. If we doesn't have to
 		 start a callback, look if we have to search another server */
+	      /* Fall through.  */
 	    case NIS_LOOKUP:
 	    case NIS_ADD:
 	    case NIS_MODIFY: