pinctrl: armada-37xx: Fix function name in the kernel doc

Kernel doc validator is not happy:

  .../pinctrl-armada-37xx.c:926: warning: expecting prototype for armada_37xx_fill_funcs(). Prototype was for armada_37xx_fill_func() instead

Fix this by updating function name in the kernel doc.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>

drivers/pinctrl/mvebu/pinctrl-armada-37xx.c

@@ -913,7 +913,7 @@ static int armada_37xx_fill_group(struct armada_37xx_pinctrl *info)
 }
 
 /**
- * armada_37xx_fill_funcs() - complete the funcs array
+ * armada_37xx_fill_func() - complete the funcs array
  * @info: info driver instance
  *
  * Based on the data available from the armada_37xx_pin_group array