saa716x: Fix GCC compiler warning
[-Wunused-function]
fix an issue with saa716x devices that would sometimes cause the dvr0 to stop sending data
This commit is imported from https://bitbucket.org/updatelee/v4l-updatelee/diff/drivers/media/pci/saa716x/saa716x_budget.c?diff2=fc3d0fc93ba3&at=master