eal/linux: remove unnecessary check for primary instance

eal/linux: remove unnecessary check for primary instance

In pci_uio_map_resource we check that we are in a primary process
before calling pci_uio_set_bus_master. However, there is already
an earlier check which means that we are always in a primary instance
at this point in the code, so the check can be removed.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: David Marchand <david.marchand@6wind.com>