It has been reported[0] that the Dell XPS 15 L502X exhibits similar
freezing behavior to the other systems[1] on this blacklist. The issue
was exposed by a prior change of mine to automatically load
dell_smm_hwmon on a wider set of XPS models. To fix the regression, add
this model to the blacklist.

[0] https://bugzilla.kernel.org/show_bug.cgi?id=211081
[1] https://bugzilla.kernel.org/show_bug.cgi?id=195751

Fixes: b8a13e5e ("hwmon: (dell-smm) Use one DMI match for all XPS models")
Cc: stable@vger.kernel.org
Reported-by: Bob Hepple <bob.hepple@gmail.com>
Tested-by: Bob Hepple <bob.hepple@gmail.com>
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Reviewed-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/a09eea7616881d40d2db2fb5fa2770dc6166bdae.1611456351.git.tommyhebb@gmail.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>