Ctx minifilter sample in 3790.1830

Gentlefolk

I notice a couple of surprise things in the ctx minifilter sample in
3790.1830 ifs kit.

First CtxPreClose is registered for IRP_MJ_FILE_SYSTEM_CONTROL instead of
IRP_MJ_CLOSE in DriverEntry ctxinit.c

{ IRP_MJ_FILE_SYSTEM_CONTROL,
FLTFL_OPERATION_REGISTRATION_SKIP_PAGING_IO,
CtxPreClose,
NULL },

Second rename processing appears to be performed for failed renames in
CtxPostSetInfo in operations.c

Cheers
Lyndon