fp5280g2: Enable host UART VGA output

This allows the machine to have the host UART output rendered to a
framebuffer and output on the BMC's graphics device up until the host
loads it's PCIe VGA driver.

Tested: Built and ran on a fp5280g2,saw that the host UART output displayed
        on the monitor.

Signed-off-by: John Wang <wangzqbj@inspur.com>
Change-Id: I7b3453140e40989b46b0e431e70287f9121fd0e7
1 file changed