fs/char_dev.c: fix incorrect documentation for unregister_chrdev_region

The current documentation for unregister_chrdev_region says that it return
a range of device numbers which is incorrect.  Instead it unregister a
range of device numbers.  Fix the documentation to make this clear.
Signed-off-by: NPartha Pratim Mukherjee <ppm.floss@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/char_dev.c

@@ -274,7 +274,7 @@ int __register_chrdev(unsigned int major, unsigned int baseminor,
 }
 
 /**
- * unregister_chrdev_region() - return a range of device numbers
+ * unregister_chrdev_region() - unregister a range of device numbers
  * @from: the first in the range of numbers to unregister
  * @count: the number of device numbers to unregister
  *