Ignore sprmTFCantSplit90 in .doc file per MS spec

Microsoft's new .doc file format specification says to ignore
sprmTFCantSplit90 in favour of (the older!) sprmTFCantSplit.

This seems to have confused the OO developer who must have been trying
to reverse engineer this without documentation: the table parsing code
gets sprmTFCantSplit90 and sprmTFCantSplit the wrong way around.

This commit removes handling of sprmTFCantSplit90 according to the
instruction in the Microsoft file format specification.
http://msdn.microsoft.com/en-us/library/dd951612.aspx

Change-Id: Ic9d3dddf102d6af0a061d2e8b68de3cf5bd9bae1
Reviewed-on: https://gerrit.libreoffice.org/8885
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>