Fix a snafu in a previous update to readelf that stopped it from printing archive...

Fix a snafu in a previous update to readelf that stopped it from printing archive member names along with the archive file name.

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This patch causes problems for glibc linknamespace tests because of how it
changes the output format of readelf on .a files.

Previously, "readelf -W -s libc.a" would produce output starting e.g.:

File: /scratch/jmyers/glibc/many8/build/glibcs/x86_64-linux-gnu/glibc/libc.a(init-first.o)

Symbol table '.symtab' contains 30 entries:

and continuing with symbol information for each object in that .a file.
After this commit, instead it starts:

File: /scratch/jmyers/glibc/many8/build/glibcs/x86_64-linux-gnu/glibc/libc.a

Symbol table '.symtab' contains 30 entries:

and every object's symbol information starts with the same File: line,
missing any information about which object's symbols (within libc.a) are
being listed.

I think the previous File: lines that said libc.a(init-first.o) etc.,
identifying the particular object within libc.a, were clearly preferable,
and the glibc linknamespace tests rely on having that information about
the individual object within libc.a.
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binutils * readelf.c (process_archive): Include member name in the
	file_name of the filedata structure.