efi_loader: GetTime() must return EFI_UNSUPPORTED

If the GetTime() runtime service is not supported, EFI_UNSUPPORTED has to
be returned.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
index 0c57d0a..40fdc0e 100644
--- a/lib/efi_loader/efi_runtime.c
+++ b/lib/efi_loader/efi_runtime.c
@@ -366,8 +366,7 @@
 			struct efi_time *time,
 			struct efi_time_cap *capabilities)
 {
-	/* Nothing we can do */
-	return EFI_DEVICE_ERROR;
+	return EFI_UNSUPPORTED;
 }
 
 /**