Add byte typedef in Kalyna's anonymous namespace to avoid issues with globally scoped byte

This check-in supports Romain Geissler's work on cleaning up our use of ::byte when it collides with std::byte. Regardless of what happens, such as removing ::byte and adding CryptoPP::byte, providing the typedef here makes Kalyna immune to the outside changes. Also see Pull Request 437 and 438.

kalyna.cpp

@@ -31,6 +31,9 @@ NAMESPACE_END
 
 ANONYMOUS_NAMESPACE_BEGIN
 
+// The typedef here is to sidestep problems with byte in the global namespace
+typedef unsigned char byte;
+
 using CryptoPP::word64;
 using CryptoPP::KalynaTab::T;
 using CryptoPP::KalynaTab::S;