[llvm/Object] - Remove ELFFile<ELFT>::getSection(const StringRef SectionName). NFC.

[grimar]

Summary

This method is dead. It was introduced in D47989,
but now the logic from D63475 is used in llvm-readobj instead.
Also it has a problem: it returns the first matching section,
even if there are multiple sections with the same name.

[MaskRay]

The declaration :274 Expected<const Elf_Shdr *> getSection(const StringRef SectionName) const; should be deleted as well.

[grimar]

In D65393#1613714, @MaskRay wrote:

The declaration :274 Expected<const Elf_Shdr *> getSection(const StringRef SectionName) const; should be deleted as well.

Thanks! I did not notice it. Going to commit soon.

include/llvm/Object/ELF.h

 ELFFile<ELFT>::getSection(uint32_t Index) const {
   auto TableOrErr = sections();
   if (!TableOrErr)
     return TableOrErr.takeError();
   return object::getSection<ELFT>(*TableOrErr, Index);
 }
 
 template <class ELFT>
-Expected<const typename ELFT::Shdr *>
-ELFFile<ELFT>::getSection(const StringRef SectionName) const {
-  auto TableOrErr = sections();
-  if (!TableOrErr)
-    return TableOrErr.takeError();
-  for (auto &Sec : *TableOrErr) {
-    auto SecNameOrErr = getSectionName(&Sec);
-    if (!SecNameOrErr)
-      return SecNameOrErr.takeError();
-    if (*SecNameOrErr == SectionName)
-      return &Sec;
-  }
-  // TODO: this error is untested.
-  return createError("invalid section name");
-}
-
-template <class ELFT>
 Expected<StringRef>
 ELFFile<ELFT>::getStringTable(const Elf_Shdr *Section) const {
   if (Section->sh_type != ELF::SHT_STRTAB)
     return createError("invalid sh_type for string table section " +
                        getSecIndexForError(this, Section) +
                        ": expected SHT_STRTAB, but got " +
                        object::getELFSectionTypeName(getHeader()->e_machine,
                                                      Section->sh_type));