Remove adobefonts override on the DSIG check

[felipesanches]

We have just updated the policy implemented on check/dsig to WARN users that they should remove the DSIG table (unless they're specially interested in still supporting OpenType features on fonts used on MS Office 2013).

See issue #3398 for more info.

This change in check behavior means the Adobe Fonts check override is not needed anymore (now it would actually be incorrect if kept unchanged):

[felipesanches]

@cjchapman FYI: I am removing that override on the adobefonts profile since the logic in the check implementation has flipped to suggest (with a WARN) the complete removal of the DSIG table instead of demanding (with a FAIL) the inclusion of a dummy signature.