Pack: Bump version after release.

Change-Id: Ib7974094c13eb314bc5bdfb85eb6757be0ef1d1b

ARM.CMSIS.pdsc

@@ -8,8 +8,10 @@
   <url>http://www.keil.com/pack/</url>
 
   <releases>
-    <release version="5.6.0-rc1">
+    <release version="5.6.1-dev0">
       Active development...
+    </release>
+    <release version="5.6.0" date="2019-07-10">
       CMSIS-Core(M): 5.3.0 (see revision history for details)
        - Added provisions for compiler-independent C startup code.
       CMSIS-Core(A): 1.1.4 (see revision history for details)