mm/mmap: fix comment of unmapped_area{_topdown}

The low_limit of unmapped area information is inclusive, and the
hight_limit is not, so make symbol to be [ instead of (.

And replace hight_limit to high_limit.

Link: https://lkml.kernel.org/r/20230111132036.801404-1-vernon2gm@gmail.com
Fixes: 3499a131 ("mm/mmap: use maple tree for unmapped_area{_topdown}")
Signed-off-by: Vernon Yang <vernon2gm@gmail.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mmap.c

@@ -1558,8 +1558,8 @@ static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags)
  * the correct alignment and offset, all from @info. Note: current->mm is used
  * for the search.
  *
- * @info: The unmapped area information including the range (low_limit -
- * hight_limit), the alignment offset and mask.
+ * @info: The unmapped area information including the range [low_limit -
+ * high_limit), the alignment offset and mask.
  *
  * Return: A memory address or -ENOMEM.
  */
@@ -1585,11 +1585,11 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 
 /**
  * unmapped_area_topdown() - Find an area between the low_limit and the
- * high_limit with * the correct alignment and offset at the highest available
+ * high_limit with the correct alignment and offset at the highest available
  * address, all from @info. Note: current->mm is used for the search.
  *
- * @info: The unmapped area information including the range (low_limit -
- * hight_limit), the alignment offset and mask.
+ * @info: The unmapped area information including the range [low_limit -
+ * high_limit), the alignment offset and mask.
  *
  * Return: A memory address or -ENOMEM.
  */