nvmem: Fix misspelling

There is no function called kstrbool().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240902142952.71639-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Matthew Wilcox

Documentation/ABI/stable/sysfs-bus-nvmem

@@ -11,7 +11,7 @@ Description:
 		Read returns '0' or '1' for read-write or read-only modes
 		respectively.
 		Write parses one of 'YyTt1NnFf0', or [oO][NnFf] for "on"
-		and "off", i.e. what kstrbool() supports.
+		and "off", i.e. what kstrtobool() supports.
 		Note: This file is only present if CONFIG_NVMEM_SYSFS
 		is enabled.