debian: explain that we're a single-threaded version

Author: feos

debian/control

@@ -16,4 +16,6 @@ Rules-Requires-Root: no
 Package: pcem
 Architecture: any
 Depends: ${shlibs:Depends}, ${misc:Depends}
-Description: PCem (short for PC Emulator) is an IBM PC emulator
+Description: PCem (short for PC Emulator) is an IBM PC emulator
+ This version of PCem has multi-threading disabled
+ in order to ensure determinism when running though libTAS.