Avoid using socklen_t.

diff --git a/configure.ac b/configure.ac
index fdfc6d5..8625ae3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1268,7 +1268,7 @@
 
 AC_C_CONST
 AC_C_INLINE
-AC_CHECK_TYPES([mode_t, off_t, pid_t, size_t, ssize_t, socklen_t, long long, fsblkcnt_t, fsfilcnt_t])
+AC_CHECK_TYPES([mode_t, off_t, pid_t, size_t, ssize_t, long long, fsblkcnt_t, fsfilcnt_t])
 
 AC_CACHE_CHECK([whether linux/input.h is for real],
 	wine_cv_linux_input_h,