Rectify sloppy PR49330 test case.

This test failed with

pr49330-2.c:10:21: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]

since it usesed unsigned long instead of __UINTPTR_TYPE__.

	PR testsuite/49330
	PR testsuite/52641
gcc/testsuite/
	* gcc.dg/torture/pr49330-2.c (foo): Use __UINTPTR_TYPE__
	instead of unsigned long.