sadf -p now displays the sensor device name for temperature,

sadf -p now displays the sensor device name for temperature,
voltage inputs and fans statistics.

The render() function was not properly used in rndr_stats.c, in particular
when the DEVICE name was to be displayed by sadf for fans, voltage inputs
and temperature statistics.
A new flag has been added (PT_USESTR) enabling the render() function to
display strings. As a consequence, sadf -d and sadf -p are now able
to display the sensor device name.
The output of sadf -d has also changed (this is no longer "device;FAN;..."
but "FAN;DEVICE;...". Same thing applies for TEMP and IN statistics).