Don't check for native dependencies as target dependencies

Don't look for cairo, fontconfig, and freetype libraries as this will
look for *target* libraries. The presence of these libraries is used as
a proxy for the gobject-introspection libraries being available for
the make-images.py script, but as this runs at build time we don't care
about target libraries at all.

Luckily there's another script, test-deps.py, which looks for the g-i
libraries so these dependencies can be removed.

meson.build

@@ -361,9 +361,6 @@ else
 endif
 
 if build_standalone and get_option('plugin_uefi_capsule')
-  cairo = dependency('cairo')
-  fontconfig = cc.find_library('fontconfig')
-  freetype = cc.find_library('freetype')
   efiboot = dependency('efiboot')
   objcopy = find_program ('objcopy')
   genpeimg = find_program ('genpeimg', required: false)