Wrong dependency: multiboot2 depends on linux

Hi,

I am trying to build a minimalistic GRUB image for multiboot2-loader-only,
and there is one wrong dependency in the current GRUB (2.13). Namely, the function

grub_loader_cmdline_size()

is defined in linux.mod. Multiboot2 has nothing to do with linux.mod, therefore
this function must be moved somewhere else (e.g. into kernel.img).

-- 
Regards,
Yuri