process: Get rid of unused dbg_printf_pevent_info()

This function is not used, just remove it.
This fixes following warning:

  CXX    process/powertop-do_process.o
process/do_process.cpp:190: warning: ‘void dbg_printf_pevent_info(event_format*, pevent_record*)’ defined but not used

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
main: 'quiet' option does not take an argument

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
main: Fix output when running workload

Currently one_measurement() function prints following message after
a successful run of the workload.

  $ sudo powertop --html --workload="sleep 1"
  Loaded 1 prior measurements
  Preparing to take measurements
  Measuring workload sleep 1.
  Unknown issue running workload!                         <-- here
  PowerTOP outputing using base filename powertop.html

It seems this was because it wrongly checks return value of system.
The return value of the system() call is the status of wait() call
so that it should be zero if things went well.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Do not call abstract_cpu::wiggle for GPU

first_cpu is uninitialized there which results in:
open("/sys/devices/system/cpu/cpu1330597711/cpufreq/scaling_max_freq", O_RDONLY)