[coreboot] Patch merged into coreboot/master: 5056b6e libpayload: Check if serial console h/w is present before using

the following patch was just integrated into master:
commit 5056b6e612569b202c96a8a54da90879f118b7d5
Author: Dave Frodin 
Date:   Sat Dec 15 13:24:02 2012 -0700

libpayload: Check if serial console h/w is present before using

The serial_io_havechar() and serial_io_getchar() functions will
    always see keystrokes available if the serial hardware isn't
    actually there. We will still output chars to non-existant
    hardware to allow virtual hardware to capture them.

Change-Id: I04e85157b6b7a185448abab352b5417a798a397a
    Signed-off-by: Dave Frodin 
    Reviewed-on: http://review.coreboot.org/2040
    Tested-by: build bot (Jenkins)
    Reviewed-by: Patrick Georgi 
    Reviewed-by: Anton Kochkov

Reviewed-By: Patrick Georgi  at Tue Dec 18 15:05:12 2012, giving +2
Build-Tested: build bot (Jenkins) at Mon Dec 17 23:39:16 2012, giving +1
Reviewed-By: Anton Kochkov  at Tue Dec 18 19:59:59 2012, giving +2
See http://review.coreboot.org/2040 for details.

-gerrit