CHROMIUM: Add #line to i/zephyr/logging/log_msg.h

Work around coreboot GCC preprocessor bug.

BUG=b:272518464
TEST=./twister --clobber-output -v -i --no-upload-cros-rdb \
  --toolchain host --coverage --coverage-formats=lcov && \
  ./util/find_non_exec_lines.py twister-out/coverage.info

Change-Id: I9826adb9af04419e20c235d315a40d623e98e997
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/zephyr/+/5262986
Tested-by: Jeremy Bettis <jbettis@chromium.org>
Commit-Queue: Tristan Honscheid <honscheid@google.com>
Auto-Submit: Jeremy Bettis <jbettis@chromium.org>
Commit-Queue: Jeremy Bettis <jbettis@chromium.org>
Reviewed-by: Tristan Honscheid <honscheid@google.com>

include/zephyr/logging/log_msg.h

@@ -3,6 +3,13 @@
  *
  * SPDX-License-Identifier: Apache-2.0
  */
+
+/*
+ * TODO(b/272518464): Work around coreboot GCC preprocessor bug.
+ * #line marks the *next* line, so it is off by one.
+ */
+#line 12
+
 #ifndef ZEPHYR_INCLUDE_LOGGING_LOG_MSG_H_
 #define ZEPHYR_INCLUDE_LOGGING_LOG_MSG_H_