Update version for v2.1.0-rc2 release

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/VERSION b/VERSION
index a162201..0a7e4e5 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.0.91
+2.0.92