Add HAVE_STRVERSCMP, guard the only usage of strverscmp with #ifdef

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/ls.c

@@ -886,9 +886,11 @@ static int sortcmp(const void *a, const void *b)
 	if (sort_opts == SORT_DIR) {
 		dif = S_ISDIR(d2->dn_mode) - S_ISDIR(d1->dn_mode);
 	} else
+#ifdef HAVE_STRVERSCMP && HAVE_STRVERSCMP == 1
 	if (sort_opts == SORT_VERSION) {
 		dif = strverscmp(d1->name, d2->name);
 	} else
+#endif
 	if (sort_opts == SORT_EXT) {
 		dif = strcmp(strchrnul(d1->name, '.'), strchrnul(d2->name, '.'));
 	}

include/platform.h

@@ -348,6 +348,7 @@ typedef unsigned smalluint;
 #define HAVE_STRCHRNUL 1
 #define HAVE_STRSEP 1
 #define HAVE_STRSIGNAL 1
+#define HAVE_STRVERSCMP 1
 #define HAVE_VASPRINTF 1
 #define HAVE_XTABS 1
 #define HAVE_MNTENT_H 1
@@ -372,6 +373,7 @@ typedef unsigned smalluint;
 # undef HAVE_STRCHRNUL
 # undef HAVE_STRSEP
 # undef HAVE_STRSIGNAL
+# undef HAVE_STRVERSCMP
 # undef HAVE_VASPRINTF
 # undef HAVE_NET_ETHERNET_H
 #endif
@@ -389,18 +391,21 @@ typedef unsigned smalluint;
 # undef HAVE_PTSNAME_R
 # undef HAVE_SYS_STATFS_H
 # undef HAVE_SIGHANDLER_T
+# undef HAVE_STRVERSCMP
 # undef HAVE_XTABS
 # undef HAVE_DPRINTF
 #endif
 
 #if defined(__digital__) && defined(__unix__)
 # undef HAVE_STPCPY
+# undef HAVE_STRVERSCMP
 #endif
 
 #if defined(ANDROID)
 # undef HAVE_DPRINTF
 # undef HAVE_STPCPY
 # undef HAVE_STRCHRNUL
+# undef HAVE_STRVERSCMP
 # undef HAVE_NET_ETHERNET_H
 #endif