regulator: fp9931: fix regulator node pointer

Sync the driver with the binding. During review process a regulators
subnode was requested but neither driver nor test setup was updated.

Fixes: 12d821b ("regulator: Add FP9931/JD9930 driver")
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Link: https://patch.msgid.link/20251223-fp9931-fix-v1-1-b19b4c1e7056@kemnade.info
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: akemnade

drivers/regulator/fp9931.c

@@ -391,6 +391,7 @@ static const struct regulator_desc regulators[] = {
 	{
 		.name = "v3p3",
 		.of_match = of_match_ptr("v3p3"),
+		.regulators_node = of_match_ptr("regulators"),
 		.id = 0,
 		.ops = &fp9931_v3p3ops,
 		.type = REGULATOR_VOLTAGE,
@@ -403,6 +404,7 @@ static const struct regulator_desc regulators[] = {
 	{
 		.name = "vposneg",
 		.of_match = of_match_ptr("vposneg"),
+		.regulators_node = of_match_ptr("regulators"),
 		.id = 1,
 		.ops = &fp9931_vposneg_ops,
 		.type = REGULATOR_VOLTAGE,
@@ -415,6 +417,7 @@ static const struct regulator_desc regulators[] = {
 	{
 		.name = "vcom",
 		.of_match = of_match_ptr("vcom"),
+		.regulators_node = of_match_ptr("regulators"),
 		.id = 2,
 		.ops = &fp9931_vcom_ops,
 		.type = REGULATOR_VOLTAGE,