src/pmstat/pmstat.c: prefer <termios.h> to <sys/termios.h>
src/pmstat/pmstat.c: prefer <termios.h> to <sys/termios.h>

According to FreeBSD, <sys/termios.h> is deprecated, so change code
to use <termios.h> in preference if both are available.

wuliming/pcp,adfernandes/pcp,wuliming/pcp,wuliming/pcp,aeg-aeg/pcpfans,wuliming/pcp,wuliming/pcp,aeg-aeg/pcpfans,wuliming/pcp,adfernandes/pcp,aeg-aeg/pcpfans,wuliming/pcp,adfernandes/pcp,aeg-aeg/pcpfans,adfernandes/pcp,wuliming/pcp,aeg-aeg/pcpfans,adfernandes/pcp,aeg-aeg/pcpfans,aeg-aeg/pcpfans,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,aeg-aeg/pcpfans