tools lib traceevent: Fix and cleanup kvm_nested_vmexit tracepoints

Fix several issues of kvm_nested_vmexit[_inject]: field width aren't
supported with pevent_print, rip was printed twice/incorrectly, SVM ISA
was hard-coded, we don't use ':' to separate field names.

Link: http://lkml.kernel.org/r/8e6c02b22ea8136c139a91c69d6cc73b8c5c184b.1388855989.git.jan.kiszka@web.de
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>