i40e: Refactor tc mqprio checks

[ Upstream commit 2313e69c ]

Refactor bitwise checks for whether TC MQPRIO is enabled
into one single method for improved readability.

Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Tested-by: Bharathi Sreenivas <bharathi.sreenivas@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Stable-dep-of: 45bb006d ("i40e: Fix ADQ rate limiting for PF")
Signed-off-by: Sasha Levin <sashal@kernel.org>