Rename otatools dependency from futility to futility-host

The futility target for host is futility-host. This is required for
ryu out of tree signing.

Change-Id: I6c06ec69f991abc23597e19dd4478774cc4d56c4
diff --git a/core/Makefile b/core/Makefile
index e0b1287..0ccea68 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -5022,7 +5022,7 @@
 
 ifeq (true,$(PRODUCT_SUPPORTS_VBOOT))
 INTERNAL_OTATOOLS_MODULES += \
-  futility \
+  futility-host \
   vboot_signer
 endif