Fix compiler warning about char signedness in buffer pointer
Fix compiler warning about char signedness in buffer pointer

Signed-off-by: David Woodhouse <b460d66aaf00c296a3db1c1d9eeafc081d5f7d70@intel.com>

cernekee/openconnect,liiir1985/openconnect,liiir1985/openconnect,atyndall/openconnect,nmav/openconnect-mine,lins05/openconnect,cernekee/openconnect,cernekee/openconnect,mtmiller/openconnect,don-johnny/openconnect,mtmiller/openconnect,certik/openconnect,liiir1985/openconnect,neshema/openconnect,certik/openconnect,atyndall/openconnect,brandt/openconnect,matlockx/openconnect,don-johnny/openconnect,mtmiller/openconnect,chadcatlett/openconnect,nmav/openconnect-mine,sihde/openconnect,neshema/openconnect,matlockx/openconnect,brandt/openconnect,matlockx/openconnect,mdutton3/OpenConnect,chadcatlett/openconnect,chadcatlett/openconnect,mtmiller/openconnect,mveplus/openconnect-client,sihde/openconnect,mdutton3/OpenConnect,lins05/openconnect,mveplus/openconnect-client,nmav/openconnect-mine,brandt/openconnect,lins05/openconnect,don-johnny/openconnect,sihde/openconnect,nmav/openconnect-mine,cernekee/openconnect,atyndall/openconnect,mveplus/openconnect-client,neshema/openconnect,mdutton3/OpenConnect,mveplus/openconnect-client,chadcatlett/openconnect,brandt/openconnect,matlockx/openconnect,atyndall/openconnect,neshema/openconnect,lins05/openconnect,certik/openconnect,don-johnny/openconnect,liiir1985/openconnect