net: qrtr: use protocol endiannes variable

sparse was unable to verify endiannes correctness due to reassignment
from le32_to_cpu to the same variable - fix this warning up by providing
a proper __le32 type and initializing it. This is not actually fixing
any bug - rather just addressing the sparse warning.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>