regulator: Add system_load constraint

Some regulators have a fixed load that isn't captured by
consumers that the kernel knows about. Add a constraint to
support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/linux/regulator/machine.h

@@ -75,6 +75,7 @@ struct regulator_state {
  *
  * @min_uA: Smallest current consumers may set.
  * @max_uA: Largest current consumers may set.
+ * @system_load: Load that isn't captured by any consumer requests.
  *
  * @valid_modes_mask: Mask of modes which may be configured by consumers.
  * @valid_ops_mask: Operations which may be performed by consumers.
@@ -112,6 +113,8 @@ struct regulation_constraints {
 	int min_uA;
 	int max_uA;
 
+	int system_load;
+
 	/* valid regulator operating modes for this machine */
 	unsigned int valid_modes_mask;