Reject path which isn't by-id link

Check if path passed to core adding or cache starting is by-id link
otherwise do not allow to use it except it is exported object's path.
Do not resolve device's by-id path during core addition or cache starting.

Signed-off-by: Slawomir Jankowski <slawomir.jankowski@intel.com>

casadm/cas_lib.h

@@ -298,6 +298,17 @@ void print_err(int error_code);
   */
 int get_dev_path(const char* disk, char* buf, size_t num);
 
+/**
+ * @brief make sure device link is unique and write sanitized version to \a dest_path
+ * 
+ * @param[in] src_path link to device
+ * @param[in] src_len length of \a src_path
+ * @param[in] dest_len max length of \a dest_path
+ * @param[out] dest_path sanitized absolute path
+ * @return 0 on success, nonzero on failure
+ */
+int set_device_path(char *dest_path, size_t dest_len, const char *src_path, size_t src_len);
+
 /**
  * @brief convert string to int
  */