fit: Fix CONFIG_FIT_SPL_PRINT

Rename CONFIG_FIT_SPL_PRINT to CONFIG_SPL_FIT_PRINT and add Kconfig
entry for it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Simon Glass <sjg@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/README b/README
index 48ed3e0..df1d5d6 100644
--- a/README
+++ b/README
@@ -2691,7 +2691,7 @@
 		use an arch-specific makefile fragment instead, for
 		example if more than one image needs to be produced.
 
-		CONFIG_FIT_SPL_PRINT
+		CONFIG_SPL_FIT_PRINT
 		Printing information about a FIT image adds quite a bit of
 		code to SPL. So this is normally disabled in SPL. Use this
 		option to re-enable it. This will affect the output of the