Change in coreboot[master]: tests: Disable -Wsource-mgr for clang

[Julius Werner (Code Review)]

Attention is currently required from: Julius Werner.
Hello build bot (Jenkins), Jakub Czapiga,

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

https://review.coreboot.org/c/coreboot/+/59814

to look at the new patch set (#2).

Change subject: tests: Disable -Wsource-mgr for clang
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tests: Disable -Wsource-mgr for clang

Unit tests fail on clang 13.0 with a cryptic

error: _timestamp_size changed binding to STB_WEAK [-Werror,-Wsource-mgr]

Probably something related to the weird things we do to mock memlayout
areas. Too lazy to track it down. Let's just disable this
(clang-specific, not properly documented) warning flag.

Signed-off-by: Julius Werner 
Change-Id: Ie49c9eef3c74592c068c899c6717621dbcb9f609
---
M payloads/libpayload/tests/Makefile.inc
M tests/Makefile.inc
2 files changed, 2 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/14/59814/2