sandbox: Move CONFIG_IO_TRACE to Kconfig

This is only used on sandbox, so select it there.

Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/Kconfig b/arch/Kconfig
index ae39716..51d46a4 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -146,6 +146,7 @@
 	select DM_SPI
 	select DM_SPI_FLASH
 	select GZIP_COMPRESSED
+	select IO_TRACE
 	select LZO
 	select OF_BOARD_SETUP
 	select PCI_ENDPOINT