test/xi2: Fix infinite loop in test_convert_XITouchOwnershipEvent

The touchid test was using a loop like:

	for(i = 1; i < 0xffffffff; i <<= 1)

When 'i' is a 32-bit variable, this infinite loops as it goes from
0x80000000 to 0. 'i' is declared as 'long', which is 32-bit in 32-bit mode.

Signed-off-by: Keith Packard <keithp@keithp.com>

test/xi2/protocol-eventconvert.c

@@ -1001,10 +1001,12 @@ test_convert_XITouchOwnershipEvent(void)
         test_XITouchOwnershipEvent(&in);
     }
 
-    for (i = 1; i <= 0xFFFFFFFF; i <<= 1)
+    for (i = 1; ; i <<= 1)
     {
         in.touchid = i;
         test_XITouchOwnershipEvent(&in);
+	if (i == (1 << 31))
+	    break;
     }
 }