efi: Make unicode printf available to the app

This is needed to show unicode strings. Enable this code in the app.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/Kconfig b/lib/Kconfig
index 10ba086..1883ac7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -52,7 +52,7 @@
 
 config CHARSET
 	bool
-	default y if UT_UNICODE || EFI_LOADER || UFS
+	default y if UT_UNICODE || EFI_LOADER || UFS || EFI_APP
 	help
 	  Enables support for various conversions between different
 	  character sets, such as between unicode representations and