Commit 21f460a5db ("ath25: fix duplicate LZMA compression"), when
attempting to restore ELF artifact generation, copiedover the raw
kernel image twice. Because of that, the .elf artifact was actually a
duplicate of raw image.
Fix that by copying over .elf suffixed kernel image instead.
Fixes: 21f460a5db ("ath25: fix duplicate LZMA compression")
Signed-off-by: Lech Perczak <lech.perczak@gmail.com>