DBCs generated with PCAN symbol explorer with MUXed values result in duplicate names

[rnd-ash]

When generating messages from a DBC that was created with PCAN explorer, and also containing MUXed signals, the resulting output file contains duplicate entries for the MUXed signal names, resulting in bad code.

I have attached both the DBC and generated Rust code to show the bug

bad_dbc_gen.zip

[nyurik]

@rnd-ash take a look at #127 - it seems the issue is no longer there even without the #126