app: aboot: Print right partition name while loading the image

The debug prints in aboot always print as loading boot image and it is
hard to know if device is booting boot image or recovery image. Update
the debug prints to print the right partition so from the logs it will
clear on what mode lk is booting into.

Change-Id: I7046ca6c08ea8a2e7189a7e54fb8db7e0a4e6ae3
1 file changed