Add UHID_DESTROY control message

This message will be sent on gamepad disconnection.

Contrary to keyboard and mouse devices, which are registered once and
unregistered when scrcpy exists, each physical gamepad is mapped with
its own HID id, and they can be plugged and unplugged dynamically.

PR #5270 <https://github.com/Genymobile/scrcpy/pull/5270>

app/tests/test_control_msg_serialize.c

@@ -370,6 +370,25 @@ static void test_serialize_uhid_input(void) {
     assert(!memcmp(buf, expected, sizeof(expected)));
 }
 
+static void test_serialize_uhid_destroy(void) {
+    struct sc_control_msg msg = {
+        .type = SC_CONTROL_MSG_TYPE_UHID_DESTROY,
+        .uhid_destroy = {
+            .id = 42,
+        },
+    };
+
+    uint8_t buf[SC_CONTROL_MSG_MAX_SIZE];
+    size_t size = sc_control_msg_serialize(&msg, buf);
+    assert(size == 3);
+
+    const uint8_t expected[] = {
+        SC_CONTROL_MSG_TYPE_UHID_DESTROY,
+        0, 42, // id
+    };
+    assert(!memcmp(buf, expected, sizeof(expected)));
+}
+
 static void test_serialize_open_hard_keyboard(void) {
     struct sc_control_msg msg = {
         .type = SC_CONTROL_MSG_TYPE_OPEN_HARD_KEYBOARD_SETTINGS,
@@ -405,6 +424,7 @@ int main(int argc, char *argv[]) {
     test_serialize_rotate_device();
     test_serialize_uhid_create();
     test_serialize_uhid_input();
+    test_serialize_uhid_destroy();
     test_serialize_open_hard_keyboard();
     return 0;
 }