Update the submodule to the head of PR in the framework repository

See Mbed-TLS/mbedtls-framework#23

Signed-off-by: Michael Schuster <michael@schuster.ms>
diff --git a/framework b/framework
index d4177eb..6a1dc7d 160000
--- a/framework
+++ b/framework
@@ -1 +1 @@
-Subproject commit d4177eb503c908e2cdc1d00277df51f898156b60
+Subproject commit 6a1dc7daa9e861fb873dd4b9f13ebfbd6f82f6dc