phy: cpcap-usb: Simplify bool conversion

Fix the following coccicheck warning:
./drivers/phy/motorola/phy-cpcap-usb.c:146:31-36: WARNING: conversion to
bool not needed here

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/1611905915-50394-1-git-send-email-yang.lee@linux.alibaba.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>