[llvm-readobj][ELF] Fall back to Address when no single relocation applies (#230653)
In a relocatable object file, --call-graph-info identifies a function by
the relocation that applies to its address field. If a field had no
relocation, nothing in the output identified the function. If the
relocation section had an invalid sh_link, the dump stopped. If a field
had more than one relocation, the first one was used silently.
In all of these cases, print the value stored in the field as Address,
as for linked files. Warn once if a call graph section has no relocation
section, and warn about each field with no relocation or more than one.
If the relocations can't be read, only that is reported.
Assisted-by: Gemini