staging:lustre: remove irq.h from socklnd.h

The header socklnd.h includes irq.h which is not need
and doesn't exist in the OpenSFS lustre branch. Having
irq.h in socklnd.h does break the build on the m68k
platform. So we can safely remove it.

Signed-off-by: James Simmons <jsimmons@infradead.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>