Silence minor nit in load-options parsing debug output

Previously when there were no load options, this would go in the debug
log:

  load-options.c:313:parse_load_options() full load options:
  include/hexdump.h:92:vhexdumpf() hexdump of a NULL pointer!

This changes it to say:

  load-options.c:315:parse_load_options() LoadOptions is empty

Signed-off-by: Peter Jones <pjones@redhat.com>

load-options.c

@@ -311,8 +311,13 @@ parse_load_options(EFI_LOADED_IMAGE *li)
 	UINT32 remaining_size;
 	CHAR16 *loader_str = NULL;
 
-	dprint(L"full load options:\n");
-	dhexdumpat(li->LoadOptions, li->LoadOptionsSize, 0);
+	if (!li->LoadOptions || !li->LoadOptionsSize) {
+		dprint(L"LoadOptions is empty\n");
+		return EFI_SUCCESS;
+	} else {
+		dprint(L"full LoadOptions:\n");
+		dhexdumpat(li->LoadOptions, li->LoadOptionsSize, 0);
+	}
 
 	/*
 	 * Sanity check since we make several assumptions about the length