Make the multi-dive files valid XML

They had multiple "root" entries (all called 'dive'), which makes baby
Jesus cry.

So just enclose them all in one root entry (called 'dives') that
magically turns it all into parseable xml.

Yeah, that really helps make the world a better place.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dives/2011-03-22.xml

@@ -1,3 +1,4 @@
+<dives>
 <dive>
 <number>1</number>
 <size>132</size>
@@ -33951,3 +33952,4 @@
    <event type="9" time="11" flags="0" value="0">surface</event>
 </sample>
 </dive>
+</dives>

dives/2011-07-16.xml

@@ -1,3 +1,4 @@
+<dives>
 <dive>
 <number>1</number>
 <size>729</size>
@@ -33891,3 +33892,4 @@
    <event type="9" time="15" flags="0" value="0">surface</event>
 </sample>
 </dive>
+</dives>

dives/2011-08-06.xml

@@ -1,3 +1,4 @@
+<dives>
 <dive>
 <number>1</number>
 <size>767</size>
@@ -34070,3 +34071,4 @@
    <event type="9" time="15" flags="0" value="0">surface</event>
 </sample>
 </dive>
+</dives>

dives/2011-08-28.xml

@@ -1,3 +1,4 @@
+<dives>
 <dive>
 <number>1</number>
 <size>266</size>
@@ -32875,3 +32876,4 @@
    <event type="9" time="14" flags="0" value="0">surface</event>
 </sample>
 </dive>
+</dives>