ixgbe: improve Atom C3000 SWFW semaphore acq

DPDK commit message

net/ixgbe/base: improve SWFW semaphore acquisition
HWSW semaphore acquisition in Atom C3000 NIC is a two stage process.
Each time two semaphore acquisitions are required. Each second semaphore
failure requires re-acquisition of first semaphore. This patch decouples
the two acquisitions preventing potentially hundreds of thousands
of unnecessary loop iterations.

Signed-off-by: Barbara Skobiej <barbara.skobiej@intel.com>

Obtained from: DPDK (99f960c)
MFC after: 1 week