> The dtb for that system has a /chosen/stdout-path of serial.
> If you want kernel output to go to a framebuffer you should change the
> device tree value, otherwise use serial.
> U-Boot will in some instances send output to both serial and
framebuffer at the same time.
> The kernel does not have the same behaviour.
This detailed and technical explanation took me quite some time to
understand that kernel message is not shown through HDMI port.
Anyway, after attaching PL2303 USB-Serial cable,
I could enter normal installation process and finish it.
In the 'INSTALL.armv7' file,
USB OTG is mentioned as no replacement for serial console,
but, I simply regarded HDMI port can be used as console,
largely from my ignorance and previous Raspberry Pi experience,
with which I used HDMI screen as console just like x86 H/W.
This is just my personal opinion, but even with comment about necessity
of serial console, and some comment against HDMI port (as well as USB
OTG port) could be helpful for newbies like me.
Sorry for wasted precious developer time.
Thank you Jonathan Gray' for detailed explanation in the reply.