Fix TARGET_PREBUILT_TAG so that get_build_var can retrieve the correct value across architectures

Change-Id: I5c1010d9caaa8d9ffaf65999fa3649c3c2be8caa
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
diff --git a/core/config.mk b/core/config.mk
index 61cd0c6..f9b7116 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -340,4 +340,12 @@
 
 INTERNAL_PLATFORM_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/public_api.xml
 
+# This is the standard way to name a directory containing prebuilt target
+# objects. E.g., prebuilt/$(TARGET_PREBUILT_TAG)/libc.so
+ifeq ($(TARGET_SIMULATOR),true)
+  TARGET_PREBUILT_TAG := $(TARGET_OS)-$(TARGET_ARCH)
+else
+  TARGET_PREBUILT_TAG := android-$(TARGET_ARCH)
+endif
+
 include $(BUILD_SYSTEM)/dumpvar.mk
diff --git a/core/envsetup.mk b/core/envsetup.mk
index 87ac2f6..f375c20 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -147,14 +147,6 @@
 TARGET_BUILD_TYPE := release
 endif
 
-# This is the standard way to name a directory containing prebuilt target
-# objects. E.g., prebuilt/$(TARGET_PREBUILT_TAG)/libc.so
-ifeq ($(TARGET_SIMULATOR),true)
-  TARGET_PREBUILT_TAG := $(TARGET_OS)-$(TARGET_ARCH)
-else
-  TARGET_PREBUILT_TAG := android-$(TARGET_ARCH)
-endif
-
 # ---------------------------------------------------------------
 # figure out the output directories