MFH: r478309

emulators/rpcs3: unbreak on FreeBSD 10.4/11.1

Utilities/types.h:94:13: error: no member named 'byte' in namespace 'std'

using std::byte;
      ~~~~~^

Utilities/types.h:773:18: error: no type named 'byte' in namespace 'std'

alignas(A) std::byte data[S];
           ~~~~~^

rpcs3/Emu/RSX/rsx_utils.h:9:10: fatal error: 'optional' file not found
#include <optional>

^~~~~~~~~~

rpcs3/Emu/RSX/Overlays/overlay_controls.h:1354:20: error: no member named 'clamp' in namespace 'std'

m_value = std::clamp(value, 0.f, m_limit);
          ~~~~~^

Reported by: pkg-fallout
Pointy hat to: jbeich
Approved by: ports-secteam blanket