payloads: add iPXE 'payload' build

We already have the ability to add a pxe rom to cbfs, but it needs to be
configured and built separately.

This moves the existing Kconfig options for PXE from device/Kconfig and
the top level Makefile.inc to payloads, and adds the option to download
and build iPXE as part of the coreboot build process.

This configures the serial output of iPXE to match coreboot's serial
port configuration by editing the .h files. iPXE doesn't give any
real build-time method of setting these configuration options.

Change-Id: I3d77b2c6845b7f5f644440f6910c3b4533a0d415
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/14085
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

0 files changed, 0 insertions, 0 deletions