[build] Make the kernel linker script to set section paddrs
[build] Make the kernel linker script to set section paddrs

By setting correctly the physical address of the program headers,
now qemu can correctly load the exOS kernel this way:

   qemu-system-i386 -m 256 -kernel ./build/elf_kernel_stripped

Clearly, this is not enough since also the ramdisk has to be loaded too.

vvaltchev/experimentOs,vvaltchev/experimentOs,vvaltchev/experimentOs,vvaltchev/experimentOs