Revert "same bootloader (grub-* and efibootmgr) packages for i386 and amd64"

This reverts commit eb9b6bedbd905595fb12c6caf6943d8f7a6bc468.

INFO  - The following packages have unmet dependencies:
INFO  -  grub-efi-amd64 : Conflicts: grub-efi-ia32 but 2.02~beta2-11 is to be installed
INFO  -  grub-efi-ia32 : Conflicts: grub-efi-amd64 but 2.02~beta2-11 is to be installed
INFO  - E: Unable to correct problems, you have held broken packages.

Conflicts:
	debian/changelog