[gimp] Fix issue with generating GIR API docs in meson

[Jehan <jehanp src gnome org>]

commit c87d6d96f233d56508cdc00916ca227156068e6e
Author: Stanislav Grinkov <43956-stanislavgrinkov users noreply gitlab gnome org>
Date:   Tue Aug 3 17:55:26 2021 +0600

    Fix issue with generating GIR API docs in meson
    
    Caused by using a non-absolute path to .gir files in
    meson.build rules
    
    Resolves: #6362

 devel-docs/g-ir-docs/meson.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/devel-docs/g-ir-docs/meson.build b/devel-docs/g-ir-docs/meson.build
index 3554b66c8b..d16bf4ebd4 100644
--- a/devel-docs/g-ir-docs/meson.build
+++ b/devel-docs/g-ir-docs/meson.build
@@ -37,7 +37,7 @@ foreach lang : [ 'python', 'gjs' ]
       '-I', meson.build_root() / 'libgimp',
       '--language=' + lang,
       '-o', '@OUTDIR@' + '/pages/' + lang + '/Gimp-' + gimp_api_version,
-      '@INPUT@'
+      meson.build_root() / '@INPUT@'
     ],
     build_by_default: true)
 
@@ -83,7 +83,7 @@ foreach lang : [ 'python', 'gjs' ]
       '-I', meson.build_root() / 'libgimp',
       '--language=' + lang,
       '-o', '@OUTDIR@' + '/pages/' + lang + '/GimpUi-' + gimp_api_version,
-      '@INPUT@'
+      meson.build_root() / '@INPUT@'
     ],
     build_by_default: true)