RID_SVXDLG_SEARCHFORM dialog convert

Change-Id: I6c5f1d83733c17a561ec2218f6260794b0c4de37
Reviewed-on: https://gerrit.libreoffice.org/8718
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>