Fix newly renamed VirtualSerial demos' include filename references so that they compile.

.../Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.c

.../Device/ClassDriver/DualVirtualSerial/DualVirtualSerial.h

Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.c

Demos/Device/ClassDriver/VirtualSerial/VirtualSerial.h

...evice/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.c

...evice/ClassDriver/VirtualSerialMouse/VirtualSerialMouse.h

Demos/Device/LowLevel/DualVirtualSerial/DualVirtualSerial.c

Demos/Device/LowLevel/DualVirtualSerial/DualVirtualSerial.h

Demos/Device/LowLevel/VirtualSerial/VirtualSerial.c

Demos/Device/LowLevel/VirtualSerial/VirtualSerial.h

Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.c

Demos/Host/ClassDriver/VirtualSerialHost/VirtualSerialHost.h

Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.h

Demos/Host/LowLevel/VirtualSerialHost/VirtualSerialHost.c

Demos/Host/LowLevel/VirtualSerialHost/VirtualSerialHost.h