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

Orig-Change-Id: I5c1010d9caaa8d9ffaf65999fa3649c3c2be8caa
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
diff --git a/core/config.mk b/core/config.mk
index 3b389fd..e20afe9 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -142,6 +142,14 @@
 TARGET_DEVICE_DIR := $(patsubst %/,%,$(dir $(board_config_mk)))
 board_config_mk :=
 
+# 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
 
 # Clean up/verify variables defined by the board config file.
diff --git a/core/envsetup.mk b/core/envsetup.mk
index e2d4d11..67fe754 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -158,14 +158,6 @@
 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