cifs: Update description about ACL permissions

There are some incorrect information about individual SMB permission
constants like WRITE_DAC can change ownership, or incomplete information to
distinguish between ACL types (discretionary vs system) and there is
completely missing information how permissions apply for directory objects
and what is meaning of GENERIC_* bits.

Also there is missing constant for MAXIMUM_ALLOWED permission.

Fix and extend description of all SMB permission constants to match the
reality, how the reference Windows SMB / NTFS implementation handles them.

Links to official Microsoft documentation related to permissions:
https://learn.microsoft.com/en-us/windows/win32/fileio/file-access-rights-constants
https://learn.microsoft.com/en-us/windows/win32/secauthz/access-mask
https://learn.microsoft.com/en-us/windows/win32/secauthz/standard-access-rights
https://learn.microsoft.com/en-us/windows/win32/secauthz/generic-access-rights
https://learn.microsoft.com/en-us/windows/win32/api/winternl/nf-winternl-ntcreatefile
https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/ntifs/nf-ntifs-ntcreatefile



Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>