Update tf-psa-crypto pointer

Signed-off-by: Felix Conway <felix.conway@arm.com>
diff --git a/tf-psa-crypto b/tf-psa-crypto
index 893f536..d66b78e 160000
--- a/tf-psa-crypto
+++ b/tf-psa-crypto
@@ -1 +1 @@
-Subproject commit 893f536dae31f358516de6d9e851da7c18f5f53e
+Subproject commit d66b78e4ad1f7a61502e3dcf62daed177facc03f