powercap: intel_rapl: Change an error pointer to NULL

commit 6b08b4e upstream.

The rapl_find_package_domain_cpuslocked() function is supposed to
return NULL on error.

This new error patch returns ERR_PTR(-EINVAL) but none of the callers
check for that so it would lead to an Oops.

Fixes: 26096ae ("powercap/intel_rapl: Fix the energy-pkg event for AMD CPUs")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/fa719c6a-8d3b-4cca-9b43-bcd477ff6655@stanley.mountain
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Dan Carpenter

drivers/powercap/intel_rapl_common.c

@@ -2156,7 +2156,7 @@ struct rapl_package *rapl_find_package_domain_cpuslocked(int id, struct rapl_if_
 		      topology_physical_package_id(id) : topology_logical_die_id(id);
 		if (uid < 0) {
 			pr_err("topology_logical_(package/die)_id() returned a negative value");
-			return ERR_PTR(-EINVAL);
+			return NULL;
 		}
 	}
 	else