x86: Don't include the BIOS emulator in TPL

We don't generally have enough space to run this, so don't build it into
TPL. This helps reduce the size of TPL.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index ca0ca10..5cd4587 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -4,9 +4,11 @@
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 
 ifndef CONFIG_X86_64
+ifndef CONFIG_TPL_BUILD
 obj-y += bios.o
 obj-y += bios_asm.o
 obj-y += bios_interrupts.o
+endif
 obj-y += string.o
 endif
 ifndef CONFIG_SPL_BUILD