Change in coreboot[master]: Makefile: Write .xcompile to $(obj)

[Raul Rangel (Code Review)]

Hello Julius Werner, build bot (Jenkins), Martin Roth, Patrick Georgi,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/28101

to look at the new patch set (#5).

Change subject: Makefile: Write .xcompile to $(obj)
......................................................................

Makefile: Write .xcompile to $(obj)

This file was being written to the root src directory. It is the only
file being written to src during a normal build, while all others are
being written to $(obj).

Since .xcompile is written into $(obj), `make clean` will now remove it.

The tegra Makefiles are outside of the normal build process, so I just
updated those Makefiles to point to the default xcompile location of a
normal buiild. The what-jenkins-does target had to be updated to support
these special targets. We generate a xcompile specifically for these
targets and pass it into the Makefile. Ideally we should get these
targets added to the main build. The COREBOOT_BUILD_DIR default value
comes from the abuild script.

The abuild missing_arches check will now generate a xcompile object into
the build directory. We could generate one file and pass it in as an
argument, but it would have required more changes.

BUG=b:112267918
TEST=ran `emerge-grunt coreboot` and `make what-jenkins-does`

Change-Id: Ia83f234447b977efa824751c9674154b77d606b0
Signed-off-by: Raul E Rangel 
---
M Makefile
M Makefile.inc
M src/soc/nvidia/tegra124/lp0/Makefile
M src/soc/nvidia/tegra210/lp0/Makefile
M util/abuild/abuild
M util/crossgcc/Makefile.inc
M util/docker/Makefile
M util/testing/Makefile.inc
8 files changed, 25 insertions(+), 18 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/01/28101/5