m5602_core: move skeletons to the .c file

The mc5602_brigde.h is included at m5602 submodules. This
causes Gcc 6.1 to complain:

drivers/media/usb/gspca/m5602/m5602_bridge.h:124:28: warning: 'sensor_urb_skeleton' defined but not used [-Wunused-const-variable=]
 static const unsigned char sensor_urb_skeleton[] = {
                            ^~~~~~~~~~~~~~~~~~~
drivers/media/usb/gspca/m5602/m5602_bridge.h:119:28: warning: 'bridge_urb_skeleton' defined but not used [-Wunused-const-variable=]
 static const unsigned char bridge_urb_skeleton[] = {
                           ^~~~~~~~~~~~~~~~~~~

Let's shut up gcc 6.1 warnings by moving those data structures
to the core, as they're used only there.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>