[MISC] Add the gitignore file

Don't track the misc/mk/config.mk. So add it to .gitignore file.

Signed-off-by: Wei Mao <maow.pok@gmail.com>
[MISC] Format the file misc/conf-env.pl file.

Use the perltidy tool to format the misc/conf-env.pl file.

Signed-off-by: Wei Mao <maow.pok@gmail.com>