Free symbol buffers if they are no longer in use
add_specific_symbols allocates a buffer to hold symbols. It should be freed only if it is no longer in use. PR binutils/23633 * objcopy.c (strip_specific_buffer): New. (strip_unneeded_buffer): Likewise. (keep_specific_buffer): Likewise. (localize_specific_buffer): Likewise. (globalize_specific_buffer): Likewise. (keepglobal_specific_buffer): Likewise. (weaken_specific_buffer): Likewise. (add_specific_symbols): Add an argument to return pointer to allocated buffer. (copy_main): Update add_specific_symbols to update pointers to allocated buffer. Free pointers to allocated buffer before return.