The base code was using native GCC macros
for endian detection. Change to portable
rte_byteorder.h based endian detection.
Fixes: 262d43fe20ee ("net/thunderx/base: add HW register definitions")
Suggested-by: Thomas Monjalon <thomas.monjalon@6wind.com>
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>