tests: add fdisk 'f' command MBR test

Signed-off-by: Karel Zak <kzak@redhat.com>
Revert "dmesg: don't use brow/yellow in output"

It will be better to support colors customization than use
ugly blue color. BTW, for example git-log uses brow/yellow too
by default.

This reverts commit 0b6fbc25990d9498956e06bfcf699fca094e24a9.
tests: update fdisk sun test

Signed-off-by: Karel Zak <kzak@redhat.com>
tests: rely on ts_init_py only

Signed-off-by: Karel Zak <kzak@redhat.com>
tests: update Py parse mountinfo test

Signed-off-by: Karel Zak <kzak@redhat.com>