doc: Update overview.txt: move USSD to implemented

move USSD from work in progress section to implemented section.

diff --git a/doc/overview.txt b/doc/overview.txt
index 2a30e0b..244b4ff 100644 (file)
--- a/doc/overview.txt
+++ b/doc/overview.txt
@@ -138,12 +138,15 @@ Current implemented features:
                operation status. Information on the Sim Toolkit feature
                list can be found in features.txt.
 
+       Supplementary Services
+
+               The Supplementary Services interface handles both recognized
+               supplementary service control string and user/network initiated
+               unstructured supplementary service data (USSD).
+
 Work in progress features:
 
-       USSD
 
-               User initiated USSD support is available, but not
-               network-initiated USSD support.
 
 Not implemented features: