GCC 12 complains about accessing a too small object.

In function 'test__AdjustPointer',
    inlined from 'func_msvcr90' at wine/dlls/msvcr90/tests/msvcr90.c:2515:5:
wine/dlls/msvcr90/tests/msvcr90.c:1556:30: warning: array subscript 30 is outside array bounds of 'void[8]' [-Warray-bounds]
 1556 |         {&obj1, (char*)&obj1 + obj.off, {0, 0, 0}},
      |                 ~~~~~~~~~~~~~^~~~~~~~~

Since we're only checking the addresses and not the underlying objects,
use uintptr_t instead of pointers.
Signed-off-by: Eric Pouech <eric.pouech@gmail.com>