net: ipa: don't be a hog in gsi_channel_poll()

The iteration count value used in gsi_channel_poll() is intended to
limit poll iterations to the budget supplied as an argument.  But
it's never updated.

Fix this bug by incrementing the count each time through the loop.
Reported-by: Sharath Chandra Vurukala <sharathv@codeaurora.com>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ipa/gsi.c

@@ -1392,6 +1392,7 @@ static int gsi_channel_poll(struct napi_struct *napi, int budget)
 	while (count < budget) {
 		struct gsi_trans *trans;
 
+		count++;
 		trans = gsi_channel_poll_one(channel);
 		if (!trans)
 			break;