hid: quirk for multi-input devices with unneeded output reports

Add new quirk HID_QUIRK_SKIP_OUTPUT_REPORTS to skip output reports
when enumerating reports on a hid-input device. Add this quirk and
HID_QUIRK_MULTI_INPUT to 0810:0001.

PantherLord Twin USB Joystick, 0810:0001 has separate input reports
for 2 distinct game controllers in the same interface, so it needs
HID_QUIRK_MULTI_INPUT. However, the device also contains one output
report per controller which is used to control the force feedback
function, and we do not want those to appear as separate input
devices as well. The simplest approach seems to be to add a quirk to
skip output reports on 0810:0001, and allow the force feedback
driver to handle those.

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index c7a6833..33b1126 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -816,6 +816,7 @@
 	struct hid_input *hidinput = NULL;
 	struct input_dev *input_dev;
 	int i, j, k;
+	int max_report_type = HID_OUTPUT_REPORT;
 
 	INIT_LIST_HEAD(&hid->inputs);
 
@@ -828,7 +829,10 @@
 	if (i == hid->maxcollection)
 		return -1;
 
-	for (k = HID_INPUT_REPORT; k <= HID_OUTPUT_REPORT; k++)
+	if (hid->quirks & HID_QUIRK_SKIP_OUTPUT_REPORTS)
+		max_report_type = HID_INPUT_REPORT;
+
+	for (k = HID_INPUT_REPORT; k <= max_report_type; k++)
 		list_for_each_entry(report, &hid->report_enum[k].report_list, list) {
 
 			if (!report->maxfield)