cdrom: don't check CDC_PLAY_AUDIO in cdrom_count_tracks()
According to MMC-3 (or any later versions) READ TOCs are mandatory
commands and have nothing to do with CDC_PLAY_AUDIO. I have no idea why
the check was put there in the first place but it now only breaks
automatic actions on certain drives.
Note that this test was only effective when ide-cdrom was being used
as sr didn't mask CDC_PLAY_AUDIO according to the capabilities.