Returns 1 when the address lies in an executable PT_LOAD segment of the
given dl_phdr_info, following FreeBSD lib/libc/gen/elf_utils.c (9.x and
11.x branches). The stub parameters become (dl_phdr_info*, void*) to
match the FreeBSD declaration; a null dl_phdr_info throws.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>