Update release_repository pin

Change-Id: I49ed0a376201767ee9c869e16dcfced364111bb7
Signed-off-by: Manuel Bottini <manuel.bottini@arm.com>

diff --git a/release_repository b/release_repository
new file mode 160000 (submodule)
index 0000000..575c81f
--- /dev/null
+++ b/release_repository
@@ -0,0 +1 @@
+Subproject commit 575c81f38edecaa662f3ee45d04ad8efded4fa81