Convert CONFIG_SHOW_BOOT_PROGRESS to Kconfig

This converts the following to Kconfig:
   CONFIG_SHOW_BOOT_PROGRESS

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/efi-x86_payload32_defconfig b/configs/efi-x86_payload32_defconfig
index 01fe5c8..b304dd7 100644
--- a/configs/efi-x86_payload32_defconfig
+++ b/configs/efi-x86_payload32_defconfig
@@ -4,6 +4,7 @@
 CONFIG_TARGET_EFI_PAYLOAD=y
 CONFIG_FIT=y
 CONFIG_FIT_SIGNATURE=y
+CONFIG_SHOW_BOOT_PROGRESS=y
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="root=/dev/sdb3 init=/sbin/init rootwait ro"
 CONFIG_PRE_CONSOLE_BUFFER=y