update the miri submodule to master

diff --git a/src/tools/miri b/src/tools/miri
index 8284b4e912baf72473c3696ce9e46cc334da18e4..e1734470e780e05a3366a2f74cfa25ea88a518a5 160000 (submodule)
--- a/src/tools/miri
+++ b/src/tools/miri
@@ -1 +1 @@
-Subproject commit 8284b4e912baf72473c3696ce9e46cc334da18e4
+Subproject commit e1734470e780e05a3366a2f74cfa25ea88a518a5