tree-wide: fix 'lenght' typo in comments and code

Some misspelled occurences of 'octet' and some comments were also fixed
as I was on it.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index f90231e..772a4fa 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -102,7 +102,7 @@
 	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB &&
 	    inode->i_size != iinfo->i_lenExtents) {
 		printk(KERN_WARNING "UDF-fs (%s): Inode %lu (mode %o) has "
-			"inode size %llu different from extent lenght %llu. "
+			"inode size %llu different from extent length %llu. "
 			"Filesystem need not be standards compliant.\n",
 			inode->i_sb->s_id, inode->i_ino, inode->i_mode,
 			(unsigned long long)inode->i_size,