kernel: fix typos and some coding style in comments

fix lenght to length

Link: http://lkml.kernel.org/r/20190521050937.4370-1-houweitaoo@gmail.com
Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 1c1ad1e..43186cc 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -188,17 +188,17 @@ extern int no_unaligned_warning;
  * enum sysctl_writes_mode - supported sysctl write modes
  *
  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
- * 	to be written, and multiple writes on the same sysctl file descriptor
- * 	will rewrite the sysctl value, regardless of file position. No warning
- * 	is issued when the initial position is not 0.
+ *	to be written, and multiple writes on the same sysctl file descriptor
+ *	will rewrite the sysctl value, regardless of file position. No warning
+ *	is issued when the initial position is not 0.
  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
- * 	not 0.
+ *	not 0.
  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
- * 	file position 0 and the value must be fully contained in the buffer
- * 	sent to the write syscall. If dealing with strings respect the file
- * 	position, but restrict this to the max length of the buffer, anything
- * 	passed the max lenght will be ignored. Multiple writes will append
- * 	to the buffer.
+ *	file position 0 and the value must be fully contained in the buffer
+ *	sent to the write syscall. If dealing with strings respect the file
+ *	position, but restrict this to the max length of the buffer, anything
+ *	passed the max length will be ignored. Multiple writes will append
+ *	to the buffer.
  *
  * These write modes control how current file position affects the behavior of
  * updating sysctl values through the proc interface on each write.