Keep original flags for create in SafeHardlinks.

Description

When open(2) is used with flags O_CREAT|O_RDWR, the file descriptor must be readable. Unfortunately O_RDWR was not passed which made read fail with EBADF and mmap to signal SIGBUS.

This issue happened with man-db for example.

This merge request, when approved, will close issue/bug: #143 (closed)

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