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/theadorable-x86-conga-qa3-e3845-pcie-x4_defconfig b/configs/theadorable-x86-conga-qa3-e3845-pcie-x4_defconfig
index 2653f71..1327edd 100644
--- a/configs/theadorable-x86-conga-qa3-e3845-pcie-x4_defconfig
+++ b/configs/theadorable-x86-conga-qa3-e3845-pcie-x4_defconfig
@@ -17,6 +17,7 @@
 CONFIG_FIT_SIGNATURE=y
 CONFIG_BOOTSTAGE=y
 CONFIG_BOOTSTAGE_REPORT=y
+CONFIG_SHOW_BOOT_PROGRESS=y
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_DISPLAY_BOARDINFO_LATE=y
 CONFIG_LAST_STAGE_INIT=y