PR12609 redux: filter out duplicate probes due to partial-inining

PR12609 redux: filter out duplicate probes due to partial-inining

Ever since gcc 4.7ish, partially-inlined functions can sometimes show
up as separate top-level functions named FOO.part.* in the ELF symbol
table, but identifed as ordinary function FOO in DWARF.  The latter
means that stap would probe both the partially inlined part of the
function, and the non-inlined second part, for a plain .function()
probe.  This new code suppresses the probe on the .part. one, based
on a symbol name heuristic.

Also RHBZ1169184.