writeprotect: add {get,set}_wp_mode()

Tested: flashrom --wp-{enable,disable,status}

Change-Id: I7b68e940f0e1359281806c98e1da119b4caf8405
Signed-off-by: Nikolai Artemiev <nartemiev@google.com>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/58483
Original-Reviewed-by: Anastasia Klimchuk <aklm@chromium.org>
Original-Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Original-Reviewed-by: Nico Huber <nico.h@gmx.de>
Original-Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/70973
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/libflashrom.h b/libflashrom.h
index db04467..c35f331 100644
--- a/libflashrom.h
+++ b/libflashrom.h
@@ -126,7 +126,9 @@
 	FLASHROM_WP_ERR_READ_FAILED = 3,
 	FLASHROM_WP_ERR_WRITE_FAILED = 4,
 	FLASHROM_WP_ERR_VERIFY_FAILED = 5,
-	FLASHROM_WP_ERR_RANGE_UNSUPPORTED = 6
+	FLASHROM_WP_ERR_RANGE_UNSUPPORTED = 6,
+	FLASHROM_WP_ERR_MODE_UNSUPPORTED = 7,
+	FLASHROM_WP_ERR_RANGE_LIST_UNAVAILABLE = 8
 };
 
 enum flashrom_wp_mode {