scripts/faddr2line: Combine three readelf calls into one

Rather than calling readelf three separate times to collect three different
types of info, call it only once, and parse out the different types of info
from its output.

Signed-off-by: Brian Johannesmeyer <bjohannesmeyer@gmail.com>
Link: https://lore.kernel.org/r/20240415145538.1938745-3-bjohannesmeyer@gmail.com


Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>