loader.efi mode command is missing modes

[tsoome]

Summary

the current mode command is assuming contiguous list of supported modes, which is not quite true, for example my qemu is supporting modes 0 and 2, but not 1.

This update adds informational line about current mode used and is fixing for loop.

Test Plan

this is the result from test in qemu:

OK mode
Current mode: 0
Mode 0: 80 columns, 25 rows
Mode 2: 100 columns, 31 rows
Select a mode with the command "mode <number>"

Also tested in vmware fusion and AMI bios.