staging: brcm80211: fix checkpatch issues in si_pmu_measure_alpclk

Patch "remove dependency between aiutils and siutils sources" introduced
several checkpatch warnings. This patch removes those in the function
si_pmu_measure_alpclk().

Cc: devel@linuxdriverproject.org
Cc: linux-wireless@vger.kernel.org
Cc: Brett Rudley <brudley@broadcom.com>
Cc: Henry Ptasinski <henryp@broadcom.com>
Cc: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>