x86: Use X86_16BIT_INIT instead of X86_RESET_VECTOR

Use this new option to control the location of 16-bit init. This will allow
us to place this in SPL if needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index d104a49..dd0e22f 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -5,10 +5,8 @@
 ifeq ($(CONFIG_EFI_APP),)
 head-y := arch/x86/cpu/start.o
 endif
-ifeq ($(CONFIG_SPL_BUILD),y)
-head-y += arch/x86/cpu/start16.o
-head-y += arch/x86/cpu/resetvec.o
-endif
+head-$(CONFIG_$(SPL_)X86_16BIT_INIT) += arch/x86/cpu/start16.o
+head-$(CONFIG_$(SPL_)X86_16BIT_INIT) += arch/x86/cpu/resetvec.o
 
 libs-y += arch/x86/cpu/
 libs-y += arch/x86/lib/
diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
index f5b8c9e..fd81310 100644
--- a/arch/x86/cpu/Makefile
+++ b/arch/x86/cpu/Makefile
@@ -9,7 +9,7 @@
 #
 
 extra-y	= start.o
-obj-$(CONFIG_X86_RESET_VECTOR) += resetvec.o start16.o
+extra-$(CONFIG_$(SPL_)X86_16BIT_INIT) += resetvec.o start16.o
 obj-y	+= interrupts.o cpu.o cpu_x86.o call64.o setjmp.o
 
 AFLAGS_REMOVE_call32.o := -mregparm=3 \
diff --git a/arch/x86/cpu/u-boot.lds b/arch/x86/cpu/u-boot.lds
index cca536b..186718d 100644
--- a/arch/x86/cpu/u-boot.lds
+++ b/arch/x86/cpu/u-boot.lds
@@ -103,7 +103,7 @@
 	/DISCARD/ : { *(.interp*) }
 	/DISCARD/ : { *(.gnu*) }
 
-#ifdef CONFIG_X86_RESET_VECTOR
+#ifdef CONFIG_X86_16BIT_INIT
 	/*
 	 * The following expressions place the 16-bit Real-Mode code and
 	 * Reset Vector at the end of the Flash ROM