Draft: [redhat] kernel.spec: increase initramfs reservation from 20MB to 40MB

When packaging the kernel we create a dummy 20MB file in the rpm build root so that installation requires at least this much free space in /boot. Unfortunately, we still get reports of boot failures due to dracut having failed to write the postinstall generated initramfs to /boot.

We did a simple analysis of the systems we have access to and found the average initramfs size to be a little over 30MB. So let's double the reservation file size to 40MB. That should protect more uses and hopefully will not create a burden on others.

Signed-off-by: Patrick Talbert ptalbert@redhat.com