Revert "phone: Enable irqbalance"

Phone runs much, much cooler without irqbalance enabled and `cat
/sys/class/thermal/thermal_zone0/temp` often reports a difference of
at least 10000, such as from 46897 to 36367. In other words, the phone
seems to be consistently 20 degrees fahrenheit cooler.

hosts/phone/configuration.nix

@@ -61,7 +61,6 @@ in
 
   services = {
     openssh.enable = true;
-    irqbalance.enable = true;
   };
 
   powerManagement = {