net: dpaa: Fix compilation Warning

Remove variables that are defined and incremented but never read.
This issue appeared in network tests[1] as:

	drivers/net/ethernet/freescale/dpaa/dpaa_eth_sysfs.c:38:6: warning: variable 'i' set but not used [-Wunused-but-set-variable]
	38 |         int i = 0;
	   |             ^

Link: https://netdev.bots.linux.dev/static/nipa/870263/13729811/build_clang/stderr [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20240712134817.913756-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/freescale/dpaa/dpaa_eth_sysfs.c

@@ -35,7 +35,6 @@ static ssize_t dpaa_eth_show_fqids(struct device *dev,
 	u32 last_fqid = 0;
 	ssize_t bytes = 0;
 	char *str;
-	int i = 0;
 
 	list_for_each_entry_safe(fq, tmp, &priv->dpaa_fq_list, list) {
 		switch (fq->fq_type) {
@@ -85,7 +84,6 @@ static ssize_t dpaa_eth_show_fqids(struct device *dev,
 
 		prev = fq;
 		prevstr = str;
-		i++;
 	}
 
 	if (prev) {