usb: dwc2: fixes host_dma logic

This patch moves the the host_dma initialization
before dwc2_set_param_dma_desc_enable() and
dwc2_set_param_dma_desc_fs_enable(). The reason being
that both function need it.

Fixes: 1205489cee75bf39 ("usb: dwc2: Get host DMA device properties")

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>