Support .asm being compiled by yasm targeted for x86_64.

Change-Id: Ia6425c38dd2f7ad2dc697213cd61b7515b9e7aff
diff --git a/core/combo/TARGET_linux-x86.mk b/core/combo/TARGET_linux-x86.mk
index e22500e..f17a514 100644
--- a/core/combo/TARGET_linux-x86.mk
+++ b/core/combo/TARGET_linux-x86.mk
@@ -147,3 +147,5 @@
 $(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 $(combo_2nd_arch_prefix)TARGET_LINKER := /system/bin/linker
+
+$(combo_2nd_arch_prefix)TARGET_GLOBAL_YASM_FLAGS := -f elf32 -m x86