hwmon: (corsair-psu) add support for critical values

Adds support for reading the critical values of the temperature sensors
and the rail sensors (voltage and current) once and caches them. Updates
the naming of the constants following a more clear scheme. Also updates
the documentation and fixes some typos. Updates is_visible and ops_read
functions to be more readable.

The new sensors output of a Corsair HX850i will look like this:
corsairpsu-hid-3-1
Adapter: HID adapter
v_in:        230.00 V
v_out +12v:   12.14 V  (crit min =  +8.41 V, crit max = +15.59 V)
v_out +5v:     5.03 V  (crit min =  +3.50 V, crit max =  +6.50 V)
v_out +3.3v:   3.30 V  (crit min =  +2.31 V, crit max =  +4.30 V)
psu fan:        0 RPM
vrm temp:     +46.2°C  (crit = +70.0°C)
case temp:    +39.8°C  (crit = +70.0°C)
power total: 152.00 W
power +12v:  108.00 W
power +5v:    41.00 W
power +3.3v:   5.00 W
curr +12v:     9.00 A  (crit max = +85.00 A)
curr +5v:      8.31 A  (crit max = +40.00 A)
curr +3.3v:    1.62 A  (crit max = +40.00 A)
Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/YFNg6vGk3sQmyqgB@monster.powergraphx.localSigned-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/corsair-psu.rst

@@ -47,19 +47,30 @@ Sysfs entries
 =======================	========================================================
 curr1_input		Total current usage
 curr2_input		Current on the 12v psu rail
+curr2_crit		Current max critical value on the 12v psu rail
 curr3_input		Current on the 5v psu rail
+curr3_crit		Current max critical value on the 5v psu rail
 curr4_input		Current on the 3.3v psu rail
+curr4_crit		Current max critical value on the 3.3v psu rail
 fan1_input		RPM of psu fan
 in0_input		Voltage of the psu ac input
 in1_input		Voltage of the 12v psu rail
+in1_crit		Voltage max critical value on the 12v psu rail
+in1_lcrit		Voltage min critical value on the 12v psu rail
 in2_input		Voltage of the 5v psu rail
-in3_input		Voltage of the 3.3 psu rail
+in2_crit		Voltage max critical value on the 5v psu rail
+in2_lcrit		Voltage min critical value on the 5v psu rail
+in3_input		Voltage of the 3.3v psu rail
+in3_crit		Voltage max critical value on the 3.3v psu rail
+in3_lcrit		Voltage min critical value on the 3.3v psu rail
 power1_input		Total power usage
 power2_input		Power usage of the 12v psu rail
 power3_input		Power usage of the 5v psu rail
 power4_input		Power usage of the 3.3v psu rail
 temp1_input		Temperature of the psu vrm component
+temp1_crit		Temperature max cirtical value of the psu vrm component
 temp2_input		Temperature of the psu case
+temp2_crit		Temperature max critical value of psu case
 =======================	========================================================
 
 Usage Notes