python3: change four shebangs to python3

Upstream-Status: Pending

Signed-off-by: Joe Slater <joe.slater@windriver.com>

--- a/tools/fio_jsonplus_clat2csv
+++ b/tools/fio_jsonplus_clat2csv
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Note: this script is python2 and python3 compatible.
 #
 # fio_jsonplus_clat2csv
--- a/tools/fiologparser.py
+++ b/tools/fiologparser.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Note: this script is python2 and python 3 compatible.
 #
 # fiologparser.py
--- a/tools/hist/fiologparser_hist.py
+++ b/tools/hist/fiologparser_hist.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """ 
     Utility for converting *_clat_hist* files generated by fio into latency statistics.
     
--- a/tools/plot/fio2gnuplot
+++ b/tools/plot/fio2gnuplot
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Note: this script is python2 and python3 compatible.
 #
 #  Copyright (C) 2013 eNovance SAS <licensing@enovance.com>