Follow-up to the NFC refactoring 43e3871a327b8e2ff57e16b46d5bc44beb430d91 and test cleanup 3cecf17065919da0a7fa9b38f37592e5462c2f85. SHF_MERGE sections with relocations are handled as InputSection (without duplicate elimination). The output section retains the original sh_entsize in non-relocatable links. This patch ports the behavior for relocatable links as well. https://github.com/ClangBuiltLinux/linux/issues/2057