sfx.c driver build failure

[Benjamin Herrenschmidt]

Hi Michael !

The sfx driver (which happens to be part of some of our test configs)
fails to build in current Linus tree on powerpc with this error:

/home/benh/kernels/linux-powerpc/drivers/net/sfc/efx.c: In function ‘efx_probe_interrupts’:
/home/benh/kernels/linux-powerpc/drivers/net/sfc/efx.c:845: error: lvalue required as unary ‘&’ oper
and

Cheers,
Ben.