htmldocs will fail, because device-drivers.tmpl references the
non-existant file 8250.c (which got renamed to 8250_core.c)

Signed-off-by: Kyle McMartin <kyle@redhat.com>

--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -227,7 +227,7 @@ X!Isound/sound_firmware.c
   <chapter id="uart16x50">
      <title>16x50 UART Driver</title>
 !Edrivers/tty/serial/serial_core.c
-!Edrivers/tty/serial/8250/8250.c
+!Edrivers/tty/serial/8250/8250_core.c
   </chapter>
 
   <chapter id="fbdev">