sparse is rightfully complaining about the fact that:

warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
   26 |   __builtin_constant_p((l) > (h)), (l) > (h), 0)))
      |                            ^
note: in expansion of macro ‘GENMASK_INPUT_CHECK’
   39 |  (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
      |   ^~~~~~~~~~~~~~~~~~~
note: in expansion of macro ‘GENMASK’
  127 |   mask = GENMASK(width, 0);
      |          ^~~~~~~

So replace the variables that go into GENMASK with plain, signed integer
types.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>