Merge pull request #44 from sifive/bump-sifive-blocks

bump sifive-blocks for GPIO IOF fix

diff --git a/sifive-blocks b/sifive-blocks
index d1d2f47f609638c43546d4a9d0a4018c73dee4bb..9052a079d404ebbfda5f01765b909c20503504ad 160000 (submodule)
--- a/sifive-blocks
+++ b/sifive-blocks
@@ -1 +1 @@
-Subproject commit d1d2f47f609638c43546d4a9d0a4018c73dee4bb
+Subproject commit 9052a079d404ebbfda5f01765b909c20503504ad