gdb: UnoReferencePrinter: prevent ambiguity problems differently
gdb: UnoReferencePrinter: prevent ambiguity problems differently

With gdb 7.5.1 the dynamic_cast may cause "Couldn't determine value's
most derived type for dynamic_cast", which isn't helpful either.
So just print the current XInterface value in case the cast fails.

Change-Id: I453b1a8eecbb056853293280195f6475f8852f2b

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core