pinctrl: aspeed: placate kernel-doc warnings

Eliminate kernel-doc warnings in drivers/pinctrl/aspeed by using
proper kernel-doc notation.

Fixes these kernel-doc warnings:

drivers/pinctrl/aspeed/pinmux-aspeed.c:61: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Query the enabled or disabled state for a mux function's signal on a pin
drivers/pinctrl/aspeed/pinctrl-aspeed.c:135: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Search for the signal expression needed to enable the pin's signal for the

Signed-off-by: Randy Dunlap <[e-mail]>
Reported-by: kernel test robot <[e-mail]>
Cc: Aditya Srivastava <[e-mail]>
Cc: Andrew Jeffery <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: Linus Walleij <[e-mail]>
Cc: [e-mail]
Acked-by: Andrew Jeffery <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/aspeed/pinctrl-aspeed.c

···
 }
 
 /**
- * Search for the signal expression needed to enable the pin's signal for the
- * requested function.
+ * aspeed_find_expr_by_name - Search for the signal expression needed to
+ * enable the pin's signal for the requested function.
  *
  * @exprs: List of signal expressions (haystack)
  * @name: The name of the requested function (needle)

drivers/pinctrl/aspeed/pinmux-aspeed.c

···
 }
 
 /**
- * Query the enabled or disabled state for a mux function's signal on a pin
+ * aspeed_sig_expr_eval - Query the enabled or disabled state for a
+ * mux function's signal on a pin
  *
  * @ctx: The driver context for the pinctrl IP
  * @expr: An expression controlling the signal for a mux function on a pin