Add a 32-bit x86_64 arch variant

The current 32-bit configuration for generic x86_64 targets inherits
some variables (SSE4 support) from the 64-bit configuration, and
overrides the make variables used for other configurations (SSSE3).
Ideally, these would be using different variables, but until then, unify
the configuration for x86_64 targets so that everything is consistent.

Bug: 28694691
Change-Id: I28efa1834f58dd2a771796c58f536d249ccf2d91
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 9ade5ac..924e523 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -9,11 +9,10 @@
 TARGET_CPU_ABI := x86_64
 TARGET_ARCH := x86_64
 TARGET_ARCH_VARIANT := x86_64
-TARGET_PRELINK_MODULE := false
 
 TARGET_2ND_CPU_ABI := x86
 TARGET_2ND_ARCH := x86
-TARGET_2ND_ARCH_VARIANT := x86
+TARGET_2ND_ARCH_VARIANT := x86_64
 
 TARGET_USES_64_BIT_BINDER := true
 
@@ -36,4 +35,4 @@
 BOARD_CACHEIMAGE_PARTITION_SIZE := 69206016
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
 BOARD_FLASH_BLOCK_SIZE := 512
-TARGET_USERIMAGES_SPARSE_EXT_DISABLED := true
\ No newline at end of file
+TARGET_USERIMAGES_SPARSE_EXT_DISABLED := true