Fix misspellings collected by members of KJ list.

Fix the misspellings of "propogate", "writting" and (oh, the shame
:-) "kenrel" in the source tree.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/include/linux/mount.h b/include/linux/mount.h
index dab69af..6d3047d 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -33,7 +33,7 @@
 
 #define MNT_SHARED	0x1000	/* if the vfsmount is a shared mount */
 #define MNT_UNBINDABLE	0x2000	/* if the vfsmount is a unbindable mount */
-#define MNT_PNODE_MASK	0x3000	/* propogation flag mask */
+#define MNT_PNODE_MASK	0x3000	/* propagation flag mask */
 
 struct vfsmount {
 	struct list_head mnt_hash;