webif/dvbapi: Do not prefix log messages comming from WebIf with "dvbapi: ".

module-dvbapi.h redefines cs_log() to include "dvbapi: " prefix.

Since module-webif.c includes module-dvbapi.h all cs_log lines coming
from webif were wrongly were prefixed with "dvbapi: ".

git-svn-id: http://streamboard.de.vu/svn/oscam/trunk@8439 4b0bc96b-bc66-0410-9d44-ebda105a78c1