tools lib traceevent: Remove hard coded install paths from pkg-config file

Install directories of header and library files are hard coded in
pkg-config template file.

They must be configurable, the Makefile should set them on the
compilation / install stage.

Signed-off-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190418211556.5a12adc3@oasis.local.home
Link: http://lkml.kernel.org/r/20190329144546.5819-1-tstoyanov@vmware.com


Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>