usb: musb: remove left-over after USB_TI_CPPI_DMA removal

Commit 32fee1df

 ("usb: musb: remove unused davinci support") removes
the config USB_TI_CPPI_DMA, but misses some left-over references in
drivers/usb/musb/musb_dma.h.

Remove the left-over dependent on this removed config.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20221031085426.17175-1-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>