[gimp] build: search only once for the addbom.sh script.

[Jehan <jehanp src gnome org>]

commit 218c78e76a53cc5ef032f4d946ca62d983493905
Author: Jehan <jehan girinstud io>
Date:   Sun Jul 31 18:25:33 2022 +0200

    build: search only once for the addbom.sh script.
    
    This avoids repeated "found: YES" output (one per installer language) on
    the project configuration.

 build/windows/installer/lang/meson.build | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/build/windows/installer/lang/meson.build b/build/windows/installer/lang/meson.build
index f7d5f13ec0..6488ecfcb7 100644
--- a/build/windows/installer/lang/meson.build
+++ b/build/windows/installer/lang/meson.build
@@ -50,6 +50,8 @@ languages = [
   { 'code': 'zh_TW', },
 ]
 
+addbom = find_program(meson.current_source_dir() / 'addbom.sh')
+
 # Then, we generate the .isl file for each language using some xsltproc magic
 foreach language : languages
   lang_code = language.get('code')
@@ -100,8 +102,7 @@ foreach language : languages
     input : [ nobom_setup_isl_tmp, 'addbom.sh' ],
     output: [ setup_isl ],
     command: [
-      find_program(meson.current_source_dir() / 'addbom.sh'),
-      '@INPUT0@', '@OUTPUT@'
+      addbom, '@INPUT0@', '@OUTPUT@'
     ],
     build_by_default: true,
   )