[M] Change in flashrom[main]: libflashrom: Add set log level functionality

[Dmitry Zhadinets (Code Review)]

Attention is currently required from: Dmitry Zhadinets, NyeonWoo Kim.

Hello Anastasia Klimchuk, NyeonWoo Kim, Peter Marheine, build bot (Jenkins),

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

https://review.coreboot.org/c/flashrom/+/87047?usp=email

to look at the new patch set (#7).

The following approvals got outdated and were removed:
Code-Review+1 by NyeonWoo Kim, Verified+1 by build bot (Jenkins)

Change subject: libflashrom: Add set log level functionality
......................................................................

libflashrom: Add set log level functionality

Before this commit, any message from Flashrom would trigger
the user's callback. This could lead to additional delays
and slow down overall Flashrom performance.

This patch adds the ability to configure the log level for
messages from Flashrom. It sets the default log level to INFO

Testing: Both unit tests and CLI tools serve as libflashrom clients.
    All unit tests run successfully.

Change-Id: I095d48b8feb5fbc950a36eb17bed0d7cb8d9df64
Signed-off-by: Dmitry Zhadinets 
---
M include/libflashrom.h
M libflashrom.c
M tests/libflashrom.c
M tests/tests.c
M tests/tests.h
5 files changed, 65 insertions(+), 11 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/47/87047/7