test: fix build on osx

test.c

@@ -1525,12 +1525,15 @@ strlncat(char *dst, size_t len, const char *src, size_t n)
   return slen + dlen;
 }
 
+#ifndef strlcat
 size_t
 strlcat(char *dst, const char *src, size_t len)
 {
   return strlncat(dst, len, src, (size_t) -1);
 }
+#endif  /* !strlcat */
 
+#ifndef strlncpy
 size_t
 strlncpy(char *dst, size_t len, const char *src, size_t n)
 {
@@ -1548,12 +1551,15 @@ strlncpy(char *dst, size_t len, const char *src, size_t n)
   assert(len > slen);
   return slen;
 }
+#endif  /* !strlncpy */
 
+#ifndef strlcpy
 size_t
 strlcpy(char *dst, const char *src, size_t len)
 {
   return strlncpy(dst, len, src, (size_t) -1);
 }
+#endif  /* !strlcpy */
 
 int
 request_url_cb (http_parser *p, const char *buf, size_t len)