Fix typos in Documentation/: 'D'-'E'

This patch fixes typos in various Documentation txts. This patch addresses
some words starting with the letters 'D'-'E'.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Documentation/aoe/todo.txt

@@ -7,7 +7,7 @@ not been observed, but it would be nice to eliminate any potential for
 deadlock under memory pressure.
 
 Because ATA over Ethernet is not fragmented by the kernel's IP code,
-the destructore member of the struct sk_buff is available to the aoe
+the destructor member of the struct sk_buff is available to the aoe
 driver.  By using a mempool for allocating all but the first few
 sk_buffs, and by registering a destructor, we should be able to
 efficiently allocate sk_buffs without introducing any potential for