zephyr: Generate initial coverage for every board

Create a new ninja target 'all.libraries' which is everything that
zephyr.elf depends on, but doesn't actually link the zephyr.elf binary.
This allows creating coverage info for boards that run on SOCs that are
too small for real coverage runs.
Enabled the HAS_COVERAGE_SUPPORT for all boards, so that the
all.libraries target will build with coverage enabled.
HAS_COVERAGE_SUPPORT can't be set in prj files, as it is not directly
user assignable. This is probably somewhat of a misuse of this flag, but
nothing depends on it except for CONFIG_COVERAGE.

Tweaked the instructions to exclude some more directories that are not
useful code, like tests and generate headers.

BUG=b:183007888
TEST=Ran commands in code_coverage.md
BRANCH=none

Change-Id: I6cf1b889b6b3883f7a76d1ae4957805bfa6d7b96
Signed-off-by: Jeremy Bettis <jbettis@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2786067
Tested-by: Jeremy Bettis <jbettis@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Jeremy Bettis <jbettis@chromium.org>

0 files changed, 0 insertions, 0 deletions