[gimp] meson: PNG support has not been an optional feature since forever!

[Jehan <jehanp src gnome org>]

commit d4a951dc6bb569df5d9704b20c2620fe76b64275
Author: Jehan <jehan girinstud io>
Date:   Wed Dec 22 19:04:35 2021 +0100

    meson: PNG support has not been an optional feature since forever!
    
    Not sure why this was set as optional in the meson build, as it was
    already mandatory in the autotools build back then (and for as long as I
    remember).

 meson.build       | 9 ++-------
 meson_options.txt | 1 -
 2 files changed, 2 insertions(+), 8 deletions(-)
---
diff --git a/meson.build b/meson.build
index 9679059747..a42159f804 100644
--- a/meson.build
+++ b/meson.build
@@ -654,13 +654,8 @@ else
 endif
 
 libpng_minver = '1.6.25'
-libpng = dependency('libpng', version: '>='+libpng_minver,
-  required: get_option('png')
-)
-if libpng.found()
-  MIMEtypes += [ 'image/png', 'image/x-icon']
-endif
-
+libpng = dependency('libpng', version: '>='+libpng_minver)
+MIMEtypes += [ 'image/png', 'image/x-icon']
 
 libmng = cc.find_library('mng', required: get_option('mng'))
 
diff --git a/meson_options.txt b/meson_options.txt
index d8df7a6276..f603708756 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -43,7 +43,6 @@ option('jpeg2000',          type: 'feature', value: 'auto', description: 'Jpeg-2
 option('jpeg-xl',           type: 'feature', value: 'auto', description: 'JPEG XL support')
 option('mng',               type: 'feature', value: 'auto', description: 'Mng support')
 option('openexr',           type: 'feature', value: 'auto', description: 'Openexr support')
-option('png',               type: 'feature', value: 'auto', description: 'PNG support')
 option('print',             type: 'boolean', value: true,   description: 'Print support')
 option('webkit-unmaintained',type: 'boolean', value: false,  description: 'Help browser and webpage plugins 
(unmaintained)')
 option('webp',              type: 'feature', value: 'auto', description: 'Webp support')