Fix assertion error in ent_info command

[Tkain]

Description

To read an entity type's datadesc map, the ent_info console command briefly instantiates an entity of that type. It then disposes of that entity by delete-ing its pointer. This causes the following assertion to fail:

source-sdk-2013/src/game/server/baseentity.cpp

Lines 456 to 462 in b8cfb12

	// In debug make sure that we don't call delete on an entity without setting
	// the disable flag first!
	// EHANDLE accessors will check, in debug, for access to entities during destruction of
	// another entity.
	// That kind of operation should only occur in UpdateOnRemove calls
	// Deletion should only occur via UTIL_Remove(Immediate) calls, not via naked delete calls
	Assert( g_bDisableEhandleAccess );

As the above comment helpfully suggests, this PR fixes this error by replacing ent_info's pointer deletion with a call to UTIL_RemoveImmediate.