console: Drop driver list in ramstage

This framework was only available in ramstage. So we had to define
console output functions separately for bootblock, romstage and SMM.
Follow-up patches will re-enable all the consoles removed here,
in a more flexible fashion, and with less lines-of-code and copy-paste.

Also the driver list is not in a well-defined order and some of the
loops could exit without visiting all drivers.

NOTE: This build has no console in ramstage.

Change-Id: Iaddc495aaca37e2a6c2c3f802a0dba27bf227a3e
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5337
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
console: Use romstage code for ramstage and SMM

Console is arch-agnostic and there is no need for separate
implementations for romstage and ramstage.

For SMM there is console only if DEBUG_SMI is selected.

Change-Id: I7028eeeff8bfbb9c8552972436b29a7508834d87
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5338
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
console: Split ROMCC helpers

These are potentially useful with GDB or SerialICE too.
Also it reduces the amount of actual code we put in romcc_console.

Change-Id: Id8c56e979660ad9f4eef39c648f68c7ec60edfba
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5339
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
build rules: Identify build stage with simple variables

Provide simple environment variables telling which stage of boot is
being built. Also move this to arch-agnostic location.

Change-Id: I8cbb5cf91f53e01c06e7d672b5be3f5c235f911d
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5410
Reviewed-by: Aaron Durbin <adurbin@google.com>
Tested-by: build bot (Jenkins)
console: Simplify the enable rules

Consoles on CBMEM and USB have somewhat complex rules and dependencies
when they can be active. Use simple variables to test which stage
of boot is being built for each console.

Change-Id: I2489e7731d07ca7d5dd2ea8b6501c73f05d6edd8
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5341
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>