Scrutinizer Auto-Fixes

@rgex requested this pull request.

This patch was automatically generated as part of the following inspection:
https://scrutinizer-ci.com/g/BitcoinPHP/BitcoinECDSA.php/inspections/7abc3519-9931-40bd-9ca3-3d82d4732037

Enabled analysis tools:
 - PHP Analyzer
 - PHP PDepend
 - PHP Similarity Analyzer
 - PHP Change Tracking Analyzer