i2c: cadence: Remove the suspended flag

The suspended flag is a flag holding the device's PM status.
The runtime framework does that for us.
Use pm_runtime_suspended call instead.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>