[10103] More cleanups in InstanceSave

[newsbot]

m src/game/InstanceSaveMgr.cpp

m src/game/InstanceSaveMgr.h

m src/game/Player.cpp

m src/shared/revision_nr.h



[10103] More cleanups in InstanceSave



* Use single function for erase element from save list.

* Make lock bool checks class local (it need be replaced by normal lock object 

in future)

* Remove redundent now friend class declarations.

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