usb: musb: Set up function pointers for DMA

Set up function pointers for DMA so get closer to
being able to build in all the DMA engines.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --cc drivers/usb/musb/am35x.c
Simple merge

diff --cc drivers/usb/musb/blackfin.c
Simple merge

diff --cc drivers/usb/musb/cppi_dma.c
Simple merge

diff --cc drivers/usb/musb/da8xx.c
Simple merge

diff --cc drivers/usb/musb/davinci.c
Simple merge

diff --cc drivers/usb/musb/jz4740.c
Simple merge

diff --cc drivers/usb/musb/musb_core.c
Simple merge

diff --cc drivers/usb/musb/musb_core.h
Simple merge

diff --cc drivers/usb/musb/musb_cppi41.c
Simple merge

diff --cc drivers/usb/musb/musb_dma.h
Simple merge

diff --cc drivers/usb/musb/musb_dsps.c
Simple merge

diff --cc drivers/usb/musb/musbhsdma.c
Simple merge

diff --cc drivers/usb/musb/omap2430.c
Simple merge

diff --cc drivers/usb/musb/tusb6010.c
Simple merge

diff --cc drivers/usb/musb/tusb6010_omap.c
Simple merge

diff --cc drivers/usb/musb/ux500.c
Simple merge

diff --cc drivers/usb/musb/ux500_dma.c
Simple merge