[source] scripts: fix build warning when overriding packages

[LEDE Commits]

blogic pushed a commit to source.git, branch master:
https://git.lede-project.org/cf458de382fc6f6a8715fadb3edf152d0196a26a

commit cf458de382fc6f6a8715fadb3edf152d0196a26a
Author: Zefir Kurtisi <zefir.kurtisi at neratec.com>
AuthorDate: Wed Oct 12 17:50:56 2016 +0200

    scripts: fix build warning when overriding packages
    
    If core packages are overridden, CONFIG_OVERRIDE_PKGS is set
    based on the scan order of packages, which eventually causes
    that config value to be modified on each build and with
    that causes the build process to warn for configuration
    being out of sync.
    
    This commit changes the CONFIG_OVERRIDE_PKGS to be sorted
    and prevents that false warning.
    
    Signed-off-by: Zefir Kurtisi <zefir.kurtisi at neratec.com>
---
 scripts/package-metadata.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/package-metadata.pl b/scripts/package-metadata.pl
index 09aed96..f5d28e4 100755
--- a/scripts/package-metadata.pl
+++ b/scripts/package-metadata.pl
@@ -351,7 +351,7 @@ sub print_package_overrides() {
 	keys %overrides > 0 or return;
 	print "\tconfig OVERRIDE_PKGS\n";
 	print "\t\tstring\n";
-	print "\t\tdefault \"".join(" ", keys %overrides)."\"\n\n";
+	print "\t\tdefault \"".join(" ", sort keys %overrides)."\"\n\n";
 }
 
 sub gen_package_config() {