load_VDMX - is the check for bCharSet == -1 necessary?

[Troy Rollo]

In dlls/gdi/freetype.c, load_VDMX refuses to process ratio records in which 
bCharSet is 0. Looking at the meaning of bCharSet and the layout of the VDMX 
table http://www.microsoft.com/OpenType/OTSpec/vdmx.htm, I can see no 
rational reason for this, and no reason appears in the code.

Since 13th December this has been generating a FIXME message for some fonts.

Does anybody know of a reason why this check is necessary? Commenting it 
hasn't hurt anything obvious.