coverity#705224 Missing break in switch, surely unintentional

Change-Id: I9ebeb373f5ab15220e3d9a4bb57db88d7a8f2714
pass sfntLen to DumpSfnts etc so sfntP reads can be checked

Change-Id: I5d8092eceb31ba251e75fe2c51b87890b8adcbf2