lib/btstack: Update to v1.5.6.2.

dpgeorge · dpgeorge · commit 825a95713ed3 · 2023-06-14T19:23:27.000+10:00
Signed-off-by: Damien George &lt;damien@micropython.org&gt;
diff --git a/lib/btstack b/lib/btstack
@@ -1 +1 @@
-Subproject commit 1635e36d06821af8b61302509e91bfcc1ade84c4
+Subproject commit 77e752abd6a0992334047a48038a5a3960e5c6bc
