[PATCH] libpayload: kconfig option for ACS or ASCII on serial

[Ulf Jordan]

Hello!

The following patch introduces a kconfig option to select between 
outputing ACS characters or their ASCII fallback approximations on the 
serial console. The default is to use ACS, i.e. the current bahaviour in 
svn HEAD.

The reason for introducing this choice is twofold: a) some terminals may 
not display ACS correctly (the current implementation is geared towards 
xterm/vt100 like terminals), and b) many (most?) terminal emulators will 
not let you cut and paste the ACS charcters in a meaningful way. 
Consequently, it is advantageous to offer the possibility of using ASCII 
fallbacks for all ACS characters.

Build and run tested under qemu with coreinfo+coreboot-v3.

/ulf