configure.ac: Don't always explicitly disable openssl
diff --git a/configure.ac b/configure.ac
index 43da458..bade848 100644
--- a/configure.ac
+++ b/configure.ac
@@ -120,7 +120,7 @@
 AC_ARG_ENABLE([openssl],
             [AS_HELP_STRING([--disable-openssl],
             [Do not look for OpenSSL])],
-            [use_openssl=no],
+            [use_openssl=$enableval],
             [use_openssl=yes])
 
 pkg_req_openssl="openssl >= 0.9.8"