dma: dw-edma: Fix build warning in dw_edma_pcie_probe()

dma: dw-edma: Fix build warning in dw_edma_pcie_probe()

The function dw_edma_pcie_probe() in dw-edma-pcie.c triggered a
frame size warning:
ld.lld:warning:
  drivers/dma/dw-edma/dw-edma-pcie.c:162:0: stack frame size (1040) exceeds limit (1024) in function 'dw_edma_pcie_probe'

This patch reduces the stack usage by dynamically allocating the
`vsec_data` structure using kmalloc(), rather than placing it on
the stack. This eliminates the overflow warning and improves kernel
robustness.

Signed-off-by: Abinash Singh <abinashsinghlalotra@gmail.com>
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/20250705160055.808165-1-abinashsinghlalotra@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>