Added patch note for file I/O speedup

--HG--
branch : SDL-1.2
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%402460

docs.html

@@ -98,6 +98,9 @@ SDL 1.2.12 is a minor bug fix release.
 <P>
 	Fixed joystick detection on Windows.
 </P>
+<P>
+	Improved performance with Win32 file I/O.
+</P>
 <P>
 	Fixed HBITMAP leak in GAPI driver.
 </P>