i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op

i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op

With the changes in the random tree, IRQF_SAMPLE_RANDOM is now a
no-op; interrupt randomness is now collected unconditionally in a very
low-overhead fashion; see commit 775f4b297b.  The IRQF_SAMPLE_RANDOM
flag was scheduled to be removed in 2009 on the
feature-removal-schedule, so this patch is preparation for the final
removal of this flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Ben Dooks" <ben-linux@fluff.org>
Cc: "Wolfram Sang" <w.sang@pengutronix.de>