can: xilinx_can: Add check for NAPI Poll function

Add check for NAPI poll function to avoid enabling interrupts
with out completing the NAPI call.

Link: https://lore.kernel.org/all/20220208162053.39896-1-srinivas.neeli@xilinx.com


Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>