bios_emulator: Don't display error when emulator terminates

As it turns out this is a normal condition, so suppress the error.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/bios_emulator/x86emu/ops.c b/drivers/bios_emulator/x86emu/ops.c
index 2bb5e2d..5752fee 100644
--- a/drivers/bios_emulator/x86emu/ops.c
+++ b/drivers/bios_emulator/x86emu/ops.c
@@ -179,7 +179,7 @@
 {
     START_OF_INSTR();
     if (M.x86.R_SP != 0) {
-	ERR_PRINTF("ILLEGAL X86 OPCODE\n");
+	DB(printf("ILLEGAL X86 OPCODE\n"));
 	TRACE_REGS();
 	DB( printk("%04x:%04x: %02X ILLEGAL X86 OPCODE!\n",
 	    M.x86.R_CS, M.x86.R_IP-1,op1));