Change the default multilib for host libraries to "both"

Change host library builds to build for both architectures to
match device builds, removing the need for LOCAL_MULTILIB := both
in all the art library makefiles.

Change-Id: I2689f67c66f5055f93941f40b3e825127f693eca
diff --git a/core/host_shared_library.mk b/core/host_shared_library.mk
index 438a9ce..e840780 100644
--- a/core/host_shared_library.mk
+++ b/core/host_shared_library.mk
@@ -6,8 +6,8 @@
 ifeq ($(HOST_PREFER_32_BIT),true)
 my_module_multilib := 32
 else
-# By default we only build host module for the first arch.
-my_module_multilib := first
+# libraries default to building for both architecturess
+my_module_multilib := both
 endif
 endif
 endif
diff --git a/core/host_static_library.mk b/core/host_static_library.mk
index 74ac2ea..52c42ef 100644
--- a/core/host_static_library.mk
+++ b/core/host_static_library.mk
@@ -6,8 +6,8 @@
 ifeq ($(HOST_PREFER_32_BIT),true)
 my_module_multilib := 32
 else
-# By default we only build host module for the first arch.
-my_module_multilib := first
+# libraries default to building for both architecturess
+my_module_multilib := both
 endif
 endif
 endif