i386: add TRACE_IRQS_OFF to entry_32.S in 'error_code'

Many exceptions use the same code path via the label 'error_code'
in entry_32.S. At this point interrupts are off, so let's inform
the tracing code of that fact before calling into C.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>