usb: musb: Remove unused function declarations

Commit 32fee1df5110 ("usb: musb: remove unused davinci support")
removed these implementations but leave declaration.

Signed-off-by: Yue Haibing <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/musb/cppi_dma.h

···
 	struct list_head		tx_complete;
 };
 
-/* CPPI IRQ handler */
-extern irqreturn_t cppi_interrupt(int, void *);
-
 struct cppi41_dma_channel {
 	struct dma_channel channel;
 	struct cppi41_dma_controller *controller;

drivers/usb/musb/musb_dma.h

···
 extern void tusb_dma_controller_destroy(struct dma_controller *c);
 
 extern struct dma_controller *
-cppi_dma_controller_create(struct musb *musb, void __iomem *base);
-extern void cppi_dma_controller_destroy(struct dma_controller *c);
-
-extern struct dma_controller *
 cppi41_dma_controller_create(struct musb *musb, void __iomem *base);
 extern void cppi41_dma_controller_destroy(struct dma_controller *c);