Make use of FileCheck numeric variable to tighten symbol address checks
in ELF/pre_init_fini_array.s test.
Thanks for the improvement. This is definitely more robust. llvm-readobj's section/symbol dump is known to be verbose. llvm-readelf -S -s is conciser/better. Can you check whether the new FileCheck feature (D60389 https://llvm.org/docs/CommandGuide/FileCheck.html#filecheck-numeric-substitution-blocks) help with llvm-readelf -S -s output?