Revert "net: netcp: MAX_SKB_FRAGS is now 'int'"

This reverts commit c5b959ee.

Reverted change is required after commit 3948b059 ("net: introduce
a config option to tweak MAX_SKB_FRAGS") which does not exist
in this tree, yet. It's only present in -next trees at the time
of writing.
Reported-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/all/20230331214444.GA1426512@dev-arch.thelio-3990X/Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/ti/netcp_core.c

@@ -2081,7 +2081,7 @@ static int netcp_create_interface(struct netcp_device *netcp_device,
 	netcp->tx_pool_region_id = temp[1];
 
 	if (netcp->tx_pool_size < MAX_SKB_FRAGS) {
-		dev_err(dev, "tx-pool size too small, must be at least %d\n",
+		dev_err(dev, "tx-pool size too small, must be at least %ld\n",
 			MAX_SKB_FRAGS);
 		ret = -ENODEV;
 		goto quit;