When calling request IRQ it is desirable to allow platforms
to specific flags for the call to request_irq. Adding irq_flags
to smsc911x_platform_config allows these flags to be passed.

Signed-off-by: Stanley.Miao <redacted>

Acked-by: Steve Glendinning <redacted>

Thanks Stanley.

I have two more arm platform smsc911x conversion patches (realview and 
pcm037) which I'll post for review shortly.  Both also depend on this 
irq_flags change, as they register their interrupts shared.  David: would 
it make sense to put this driver patch into the arm tree?

Steve