utilize "/usr/bin/env perl" in perl scripts

When utilizing /usr/bin/perl, this expands to the full path of your
filesystem build. i.e. something like this:

/home/andrewg/Code/openbmc/build/witherspoon/tmp/work/x86_64-linux/mrw-perl-tools-native/1.0+gitAUTOINC+65ca8e19c4-r1/recipe-sysroot-native/usr/bin/perl

This now exceeds the allowed size by yocto:
"maximum shebang size exceeded, the maximum size is 128."

There are ways to disable this check in yocto, and we probably have a
case to argue this upstream, but our use in OpenBMC of perl is pretty
limited so the easiest solution is to just move the perl scripts over to
using /usr/bin/env. Half the perl scripts in this repo already do this.

Tested:
- Verified new yocto now builds this repo

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I1c6dfc49a9a1d5ace0d0b9fdd4fa7a0abdee033e
diff --git a/gen_callouts.pl b/gen_callouts.pl
index b23a8bb..01f93c0 100755
--- a/gen_callouts.pl
+++ b/gen_callouts.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_fru_properties.pl b/gen_fru_properties.pl
index 8479fc9..970a074 100755
--- a/gen_fru_properties.pl
+++ b/gen_fru_properties.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_ipmi_fru.pl b/gen_ipmi_fru.pl
index 9d0b6f0..94286f2 100644
--- a/gen_ipmi_fru.pl
+++ b/gen_ipmi_fru.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_ipmi_sel.pl b/gen_ipmi_sel.pl
index 07c9ccd..0da8be8 100755
--- a/gen_ipmi_sel.pl
+++ b/gen_ipmi_sel.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_ipmi_sensor.pl b/gen_ipmi_sensor.pl
index 01825d0..882f5fb 100755
--- a/gen_ipmi_sensor.pl
+++ b/gen_ipmi_sensor.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_openpower_fru.pl b/gen_openpower_fru.pl
index beb19aa..57851d6 100755
--- a/gen_openpower_fru.pl
+++ b/gen_openpower_fru.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/gen_path_callouts.pl b/gen_path_callouts.pl
index 0ea238e..163ad22 100755
--- a/gen_path_callouts.pl
+++ b/gen_path_callouts.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # This script is used for generating callout lists from the MRW for devices
 # that can be accessed from the BMC.  The callouts have a location code, the
diff --git a/print_inventory.pl b/print_inventory.pl
index 755f441..b3db9f0 100755
--- a/print_inventory.pl
+++ b/print_inventory.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;
diff --git a/print_targets.pl b/print_targets.pl
index 9d931c0..fd62c78 100755
--- a/print_targets.pl
+++ b/print_targets.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 use strict;
 use warnings;