Update to libnitrokey v3.6

This patch updates libnitrokey from version 3.5 to version 3.6, causing
these changes:

- New constants:
  - `NK_device_model_NK_LIBREM` (`NK_device_model` enum)
- New structures:
  - `NK_config`
- New functions:
  - `NK_device_serial_number_as_u32`
  - `NK_write_config_struct`
  - `NK_free_config`
  - `NK_read_config_struct`
  - `NK_free_password_safe_slot_status`
- Deprecated functions:
  - `NK_set_unencrypted_read_only`
  - `NK_set_unencrypted_read_write`

1 files changed, 1 insertions, 1 deletions

diff --git a/build.rs b/build.rs
index 24fdf0a..a6ae9fc 100644
--- a/build.rs
+++ b/build.rs
@@ -26,7 +26,7 @@ impl fmt::Display for Version {
 
 const LIBNITROKEY_VERSION: Version = Version {
     major: 3,
-    minor: 5,
+    minor: 6,
     patch: None,
 };