[oe] [meta-oe] Change bluetooth.h to compile in strict C

[Ankur Tyagi]

Hi,

qtconnectivity and qtsystems fail to build because of Bluetooth.h
compilation error.

It is fixed in :
​
http://git.kernel.org/cgit/bluetooth/bluez.git/commit/?id=cf52a40302d0d20ccca22a7a1f53e46ef8abfca8
​


Please include this patch in bluez recipe.

thanks
Ankur