[gegl] meson: revert babl/meson build requirement

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 9147e05b2f6d6769d24f984e574f054d200ff970
Author: Øyvind Kolås <pippin gimp org>
Date:   Thu Mar 25 17:07:35 2021 +0100

    meson: revert babl/meson build requirement
    
    Building with latest babl is highly recommended, older distros that want
    to build GIMP should perhaps consider patching the *babl build* to work
    with older meson.

 docs/NEWS.txt | 27 +++++++++++++++++++++++++++
 meson.build   |  4 ++--
 2 files changed, 29 insertions(+), 2 deletions(-)
---
diff --git a/docs/NEWS.txt b/docs/NEWS.txt
index 97b41afc0..034413352 100644
--- a/docs/NEWS.txt
+++ b/docs/NEWS.txt
@@ -1,3 +1,30 @@
+GEGL-0.5.30 2021-03-26
+----------------------
+
+Core:
+~~~~~
+
+Build:
+~~~~~~
+
+Upload meson logs as artifcats, use release and debugoptimized build types.
+pin glibc package in arch CI build to a version before it hard depends on linux 4.4.
+Reduce babl requirement to 0.1.78, it is *highly* recommended to build with
+a newer babl though despite it being what wants to increase the meson
+version requirement.
+
+Operations:
+~~~~~~~~~~~
+  fattal02 : ensure gaussian pyramid has at least one level.
+  paint-select, operation by Thomas Manni.
+  negative-darkroom, This operation is for artists who use hybrid workflow
+technique of analog photography. After scanning a developed negative, this
+operation is used to invert the scan to create a positive image by simulating
+the light behaviour of darkroom enlarger and common photographic papers.
+
+
+
+
 GEGL-0.4.28 2020-12-20
 ----------------------
 
diff --git a/meson.build b/meson.build
index e38ecd2ce..49a885119 100644
--- a/meson.build
+++ b/meson.build
@@ -2,7 +2,7 @@ project('gegl',
   'c', 'cpp',
   license: 'GPL3+',
   version: '0.4.29',
-  meson_version: '>=0.54.0',
+  meson_version: '>=0.50.0',
   default_options: [
     'c_std=gnu11',
     'cpp_std=gnu++14',
@@ -162,7 +162,7 @@ math    = cc.find_library('m', required: false)
 libdl   = cc.find_library('dl', required : false)
 thread  = dependency('threads')
 
-babl      = dependency('babl',          version: '>=0.1.84')
+babl      = dependency('babl',          version: '>=0.1.78')
 glib      = dependency('glib-2.0',      version: '>=2.44.0')
 gobject   = dependency('gobject-2.0',   version: '>=2.44.0')
 gmodule   = dependency('gmodule-2.0',   version: '>=2.44.0')