x86: gen_idt.py: Fix broken error() call in update_irq_vec_map()

Accidentally passed two arguments instead of one. Fixes this pylint
error:

    arch/x86/gen_idt.py:132:8: E1121: Too many positional arguments for
    function call (too-many-function-args)

Fixing pylint warning for a CI check.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>