[gdk-pixbuf/ebassi/for-master] build: Use old syntax for fallback dependencies

[Matthias Clasen <matthiasc src gnome org>]

commit d283ffcd6b3b7a4ef2133af1248a7240d9a5d2f4
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Apr 16 15:31:29 2021 -0400

    build: Use old syntax for fallback dependencies
    
    With meson 0.56, this can be done more elegantly with
    allow_fallback and a [provide] section in the wrap
    files, but with 0.55, we need to explictly mention
    the variable names in the meson file.

 meson.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/meson.build b/meson.build
index 738e447d4..c07e9cb08 100644
--- a/meson.build
+++ b/meson.build
@@ -297,7 +297,7 @@ if get_option('png')
     # that will bypass --wrap-mode and cause issues for distro packagers.
     # See: https://mesonbuild.com/Reference-manual.html#dependency
     if not png_dep.found()
-      png_dep = dependency('', required: false, fallback: 'libpng')
+      png_dep = dependency('', required: false, fallback: ['libpng', 'png_dep'])
       if png_dep.found()
         enabled_loaders += 'png'
         loaders_deps += png_dep
@@ -342,7 +342,7 @@ if get_option('jpeg') and not native_windows_loaders
   # then use pkg-config, and if that fails, fall back to the
   # wrap
   if not enabled_loaders.contains('jpeg')
-    jpeg_dep = dependency('libjpeg', required: false, fallback: 'libjpeg')
+    jpeg_dep = dependency('libjpeg', required: false, fallback: ['libjpeg', 'jpeg_dep'])
 
     if jpeg_dep.found()
       enabled_loaders += 'jpeg'