symbols: prefix static symbols with their source file names

symbols: prefix static symbols with their source file names

This requires adjustments to the tool generating the symbol table and
its as well as nm's invocation.

Note: Not warning about duplicate symbols in the EFI case for now, as
a binutils bug causes misnamed file name entries to appear in EFI
binaries' symbol tables when the file name is longer than 18 chars.
(Not doing so also avoids other duplicates getting printed twice.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>