loader: efi: Bump the heap from 64 to 128MB.

[manu]

Summary

As we now alloc the framebuffer a lot of memory is consumed by it, bump the
heapsize so we have enough memory to do other things (like preloading a kernel
from tftp).

MFC after: 2 weeks
Sponsored by: Beckhoff Automation GmbH & Co. KG

[tsoome]

I think, we probably should allocate shadow fb outside of heap (for UEFI loader, with BS->AllocatePages()), however, this is a bit complicated with BIOS loader.

[manu]

In D33598#759115, @tsoome wrote:

I think, we probably should allocate shadow fb outside of heap (for UEFI loader, with BS->AllocatePages()), however, this is a bit complicated with BIOS loader.

In the meantime even using a 1280x1080 screen is enough to break tftp preloading so I don't see some quicker solution.

[tsoome]

In D33598#759117, @manu wrote:

In D33598#759115, @tsoome wrote:

I think, we probably should allocate shadow fb outside of heap (for UEFI loader, with BS->AllocatePages()), however, this is a bit complicated with BIOS loader.

In the meantime even using a 1280x1080 screen is enough to break tftp preloading so I don't see some quicker solution.

I did create alternate option: https://reviews.freebsd.org/D33600 - if you could test it... :)