AudioReencodeBuffer: Remove m_bits which isn't used anywhere

Refs Coverity ID 746889
AudioTest: also initialise m_button missed in 54328bd25

There's a code path in the ctor where m_button could be left uninitialised and
that upsets Coverity. Refs ID 746876.
AudioAdvancedSettings: also remove m_triggerMPCM missed in 54328bd25

Refs Coverity ID 700946.
DTC::BlurayInfo: fix some uninitialised variables in the ctors

Fixes Coverity IDs 700892 and 700893.
ChannelInfoList: fix coverity ID 700894 Uninitialized scalar field

In DTC::?ChannelInfoList::ChannelInfoList(): A scalar field is not
initialized by the constructor.
RecRuleList: fix coverity ID 700895 Uninitialized scalar field

In DTC::RecRuleList::RecRuleList(): Several scalar fields are not initialized
by the constructor.
ViewScheduled: fix coverity ID 746886 Uninitialized pointer field

In ViewScheduled::ViewScheduled(): Several fields are not initialized in the
constructor.
CustomPriority: fix coverity ID 746878 Uninitialized pointer field

In CustomPriority::CustomPriority(): Several fields are not initialized
in the constructor.
CustomEdit: fix coverity ID 746877 Uninitialized pointer field

In CustomEdit::CustomEdit(): Several pointer fields are not initialized
in the constructor.
GuideGrid: fix coverity ID 1023903 Uninitialized pointer field

In GuideGrid::GuideGrid(): Several fields are not initialized in the
constructor.
LCDServer: fix coverity ID 746888 Uninitialized pointer field

In LCDServer::LCDServer(): There is a code path where m_lastSocket is not
initialized in the constructor.
LCDProcClient: fix coverity ID 746887 Uninitialized scalar field

In LCDProcClient::LCDProcClient(): Several fields are not initialized by the
constructor.
LCDProcClient: rename all the member variables to match our coding standards
VideoDialog: fix coverity ID 746884 Uninitialized pointer field

In VideoDialog::VideoDialog(): Several pointer fields are not initialized in
the constructor.
IdleScreen: fix coverity ID 746880 Uninitialized pointer field

Remove m_upcomingList that Coverity is saying is uninitialised it's currently
unused.
PlaybackBox: fix coverity ID 1023904 Uninitialized pointer field

In PlaybackBox::PlaybackBox(): Several fields are not initialized in the
constructor.
MediaRenderer: fix coverity ID 700947 Uninitialized pointer field

In MediaRenderer::MediaRenderer(): There was a couple of code paths in the ctor
where m_pUPnpCMGR could end up being uninitialized.
MHListGroup: fix coverity ID 700819 Uninitialized scalar field

In MHListGroup::MHListGroup(): Several scalar fields are not initialized
by the constructor.
MHScene: fix coverity ID 700817 Uninitialized scalar field

In MHScene::MHScene(): Several scalar fields are not initialized by the
constructor.
Fix Cppcheck issue. QPoint is default initialised to 0,0 so it's not necessary to do it explicitly.