Drop zapping values in the Zap* option descriptions

The descriptions for Zap* options include the values that are used for zapping. Since these are not mechanically substituted from globalDefinitions.hpp, they can get desynced with the actual values used. For example, JDK-8184762 changed the pattern for ZapStackSegments, but never updated the option.

We should either drop the values from the options descriptions, or sync them with the definitions. Since we cannot mechanically check that zapping code actually uses the correct value, it seems simpler to just drop the zapping values from the descriptions.

The developers can always look into the globalDefinitions to find the exact value used on the particular zapping path:
 https://github.com/openjdk/jdk/blob/594e5161b48382d61509b4969bc8f52c3c076452/src/hotspot/share/utilities/globalDefinitions.hpp#L961-L974