dmaengine: dw-edma: Fix build error without CONFIG_PCI_MSI

If CONFIG_PCI_MSI is not set, building with CONFIG_DW_EDMA
fails:

drivers/dma/dw-edma/dw-edma-core.c: In function dw_edma_irq_request:
drivers/dma/dw-edma/dw-edma-core.c:784:21: error: implicit declaration of function pci_irq_vector; did you mean rcu_irq_enter? [-Werror=implicit-function-declaration]
   err = request_irq(pci_irq_vector(to_pci_dev(dev), 0),
                     ^~~~~~~~~~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: e63d79d1

 ("dmaengine: Add Synopsys eDMA IP core driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>