-Wdeprecated-declarations: first deprecated in OS X 10.10

vcl/osx/printaccessoryview.mm:362:37: warning: 'NSScaleProportionally' is deprecated: first deprecated in OS X 10.10 - Use NSImageScaleProportionallyDown instead [-Wdeprecated-declarations]

Available in OS X v10.0 and later. Deprecated in OS X v10.10.
enum {
   NSScaleProportionally = 0,
   NSScaleToFit,
   NSScaleNone
};

Available in OS X v10.5 and later.
enum {
   NSImageScaleProportionallyDown = 0,
   NSImageScaleAxesIndependently,
   NSImageScaleNone,
   NSImageScaleProportionallyUpOrDown
};

Change-Id: I457196e3e8f2ebcc10e9e0fa87755e5e3dba207c
Reviewed-on: https://gerrit.libreoffice.org/10121
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>