NTPsec on MIPSbe

[Trevor N.]

	I just finished testing the refclocks supported by the Trimble
driver on a sparc64 machine. The configure was able to set 
WORDS_BIGENDIAN 1
without any problem. I didn't notice any runtime problems besides
what's likely due to serial port delays, but there were some warnings
during the build that I didn't see with an amd64 machine ("cast
increases required alignment of target type").