This change fixes the handling of versions in elf_find_func_offset.
In the previous implementation, we incorrectly assumed that the
version information would be present in the string found in the
string table.
We now look up the correct version string in the version symbol
table before constructing the full name and then comparing.
This patch adds support for both name@version and name@@version to
match output of the various elf parsers.
Signed-off-by: Espen Grindhaug <espen.grindhaug@xxxxxxxxx>