thermal: armada: Fix possible overflow in the Armada 380 thermal sens…

…or formula

Update the coefficients so the calculation will not overrun the
unsigned long 32bits boundary

Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Reviewed-by: Victor Axelrod <victora@marvell.com>
Reviewed-by: Neta Zur Hershkovits <neta@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

drivers/thermal/armada_thermal.c

@@ -224,9 +224,9 @@ static const struct armada_thermal_data armada380_data = {
 	.is_valid_shift = 10,
 	.temp_shift = 0,
 	.temp_mask = 0x3ff,
-	.coef_b = 2931108200UL,
-	.coef_m = 5000000UL,
-	.coef_div = 10502,
+	.coef_b = 1172499100UL,
+	.coef_m = 2000096UL,
+	.coef_div = 4201,
 	.inverted = true,
 };