hwmon: (pmbus) fix a typo in Kconfig SENSORS_IR35221 option

Fix a typo in SENSORS_IR35221 option: module name should be "ir35221"
instead of "ir35521".

Fixes: 8991ebd9 ("hwmon: (pmbus) Add client driver for IR35221")

Cc: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: NTao Ren <rentao.bupt@gmail.com>
Link: https://lore.kernel.org/r/20200702221349.18139-1-rentao.bupt@gmail.comSigned-off-by: NGuenter Roeck <linux@roeck-us.net>

drivers/hwmon/pmbus/Kconfig

@@ -71,7 +71,7 @@ config SENSORS_IR35221
 	  Infineon IR35221 controller.
 
 	  This driver can also be built as a module. If so, the module will
-	  be called ir35521.
+	  be called ir35221.
 
 config SENSORS_IR38064
 	tristate "Infineon IR38064"