Fix length parameter in send_feature_report
Fix length parameter in send_feature_report

The length sent to hid_send_feature_report should always be the number of bytes in the buffer. send_feature_report is currently only sending the number of bytes after the report_id. From the hidapi documentation:

"Since the Report ID is mandatory, calls to hid_send_feature_report() will always contain one more byte than the report contains. For example, if a hid report is 16 bytes long, 17 bytes must be passed to hid_send_feature_report(): the Report ID (or 0x0, for devices which do not use numbered reports), followed by the report data (16 bytes). In this example, the length passed in would be 17."
jbaiter/hidapi-cffi