[PATCH OSSTEST] Osstest/TestSupport: Hide $ho->{Toolstack} from casual use

[Ian Campbell <ian.campbell@citrix.com>]

This should only be accessed via toolstack($ho), which is responsible
for caching the value. Rename the field to _Toolstack to deter code
from using it.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 Osstest/TestSupport.pm | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Osstest/TestSupport.pm b/Osstest/TestSupport.pm
index 84e86fd..0370129 100644
--- a/Osstest/TestSupport.pm
+++ b/Osstest/TestSupport.pm
@@ -2076,11 +2076,11 @@ sub guest_vncsnapshot_stash ($$$$) {
 
 sub toolstack ($) {
     my ($ho) = @_;
-    return $ho->{Toolstack} if $ho->{Toolstack};
+    return $ho->{_Toolstack} if $ho->{_Toolstack};
 
     my $tsname= $r{toolstack} || 'xend';
-    $ho->{Toolstack}= get_host_method_object($ho, 'Toolstack', $tsname);
-    return $ho->{Toolstack};
+    $ho->{_Toolstack}= get_host_method_object($ho, 'Toolstack', $tsname);
+    return $ho->{_Toolstack};
 }
 
 sub authorized_keys () {
-- 
2.1.4