curl_strequal.3: fix typo in SYNOPSIS

Reported-by: Jesse Chisholm

Fixes #1623
diff --git a/docs/libcurl/curl_strequal.3 b/docs/libcurl/curl_strequal.3
index a745f7e..e9cf803 100644
--- a/docs/libcurl/curl_strequal.3
+++ b/docs/libcurl/curl_strequal.3
@@ -5,7 +5,7 @@
 .\" *                            | (__| |_| |  _ <| |___
 .\" *                             \___|\___/|_| \_\_____|
 .\" *
-.\" * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
 .\" *
 .\" * This software is licensed as described in the file COPYING, which
 .\" * you should have received as part of this distribution. The terms
@@ -27,7 +27,7 @@
 .sp
 .BI "int curl_strequal(char *" str1 ", char *" str2 ");"
 .sp
-.BI "int curl_strenqual(char *" str1 ", char *" str2 ", size_t " len ");"
+.BI "int curl_strnequal(char *" str1 ", char *" str2 ", size_t " len ");"
 .SH DESCRIPTION
 The
 .B curl_strequal()