dmaengine: shdma: increase size of 'dev_id'

[ Upstream commit 404290240827c3bb5c4e195174a8854eef2f89ac ]

We seem to have hit warnings of 'output may be truncated' which is fixed
by increasing the size of 'dev_id'

drivers/dma/sh/shdmac.c: In function ‘sh_dmae_probe’:
drivers/dma/sh/shdmac.c:541:34: error: ‘%d’ directive output may be truncated writing between 1 and 10 bytes into a region of size 9 [-Werror=format-truncation=]
  541 |                          "sh-dmae%d.%d", pdev->id, id);
      |                                  ^~
In function ‘sh_dmae_chan_probe’,
    inlined from ‘sh_dmae_probe’ at drivers/dma/sh/shdmac.c:845:9:
drivers/dma/sh/shdmac.c:541:26: note: directive argument in the range [0, 2147483647]
  541 |                          "sh-dmae%d.%d", pdev->id, id);
      |                          ^~~~~~~~~~~~~~
drivers/dma/sh/shdmac.c:541:26: note: directive argument in the range [0, 19]
drivers/dma/sh/shdmac.c:540:17: note: ‘snprintf’ output between 11 and 21 bytes into a destination of size 16
  540 |                 snprintf(sh_chan->dev_id, sizeof(sh_chan->dev_id),
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  541 |                          "sh-dmae%d.%d", pdev->id, id);
      |                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>