Mux values starting with Alpha in ID fails to convert.

[guy-radford-sunswap]

When setting a value for a Mux, if the value starts with an alpha, cantools, throws an error:

SYM: "Invalid syntax at line 3878, column 30: "Mux=FATAL_BAD_FAULT_TYPE 0,8 >>!<<C0h""

This version fails, the Mux line ends with the value C0h

[EDR_EVENT_FATAL]
ID=127h // Fatal event notification
Len=5
Mux=FATAL_BAD_FAULT_TYPE 0,8 C0h
Var=Context unsigned 8,32 // Fatal event context

If we change the Mux value to 90h (starting with a number) the error is not thrown.

[EDR_EVENT_FATAL]
ID=127h // Fatal event notification
Len=5
Mux=FATAL_BAD_FAULT_TYPE 0,8 90h
Var=Context unsigned 8,32 // Fatal event context

[swaldhoer]

This is basically the same problem as #458.