check_elf_alignment.sh: check all files, warn some

Makes check_elf_alignment.sh check all files which report
themselves to be ELF, even if they aren't executable or name
themselves something weird.

This also provides a warning on .apk and .apex files -
you must call them directly.

Bugs: me
Test: run on system/extras, run on .apk
Change-Id: I73c5457e15c1558e6f84a8538d4cd02c59c39f7b
1 file changed