ptxed: print file handling errors
ptxed: print file handling errors

All errors with file operations result in -pte_bad_config.  This makes
it impossible to see what exactly went wrong.

Add error messages.

Change-Id: Ic02016ab5558845e9f12de8797616453e0f6f2d1
Signed-off-by: Markus Metzger <5f675b2b36595f90898e014b548ff7d9bbff2ab7@intel.com>

01org/processor-trace,pombreda/processor-trace,hoangt/processor-trace,breadbaconic/processor-trace,01org/processor-trace,drupalhunter-team/processor-trace,andikleen/processor-trace,andikleen/processor-trace,01org/processor-trace,pombreda/processor-trace,breadbaconic/processor-trace,shadown/processor-trace,shadown/processor-trace,hoangt/processor-trace,drupalhunter-team/processor-trace