Solution: Check CONFIG_DRM_I915_KMS
I checked CONFIG_DRM_I915_KMS (CONFIG_DRM_I915 was already checked) and built the kernel.
This the only change I had to do on defconfig (ARCH=x86)
Upon boot completion there is no flickering.
4 Pingouins are displayed at the top of the screen.
The resolution is higher than 80x25
Not sure this is an optimal solution. According to the help:
Choose this option if you want kernel modesetting enabled by default,
and you have a new enough userspace to support this. Running old
userspaces with this enabled will cause pain. Note that this causes
the driver to bind to PCI devices, which precludes loading things