Documentation: xfs: Fix typo

In "Y+P" of this line, there are two non-ASCII characters(0xd9 0x8d)
following behind the 'Y'.  Shown as a small '=' under the '+' in VIM
and a '賺' in webpage[1].

I think it's a mistake and remove these strange characters.

[1]: https://www.kernel.org/doc/Documentation/filesystems/xfs-delayed-logging-design.txtSigned-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/filesystems/xfs-delayed-logging-design.txt

@@ -34,7 +34,7 @@ transaction:
 	   D			A+B+C+D		X+n+m+o
 	    <object written to disk>
 	   E			   E		   Y (> X+n+m+o)
-	   F			  E+F		  Yٍ+p
+	   F			  E+F		  Y+p
 
 In other words, each time an object is relogged, the new transaction contains
 the aggregation of all the previous changes currently held only in the log.