build_haiku_image: filter duplicate packages

Resolving the package dependencies for system might yield packages that
are already given for common. Filter those out of the list for common
before resolving the common dependencies.

build/scripts/build_haiku_image

@@ -147,6 +147,18 @@ else
 fi
 
 
+is_in_list()
+{
+	local element
+	for element in $2; do
+		if [ "$1" = "$element" ]; then
+			return 0
+		fi
+	done
+	return 1
+}
+
+
 extractFile()
 {
 	# extractFile <archive> <directory> <extractedSubDir>
@@ -279,6 +291,18 @@ if [ -n "$resolvePackageDependencies" ]; then
 		systemPackages="$systemPackages $packageFilePath"
 	done
 
+	# Remove packages from the list for common, that are already in the package
+	# list for system.
+	unfilteredCommonPackages="$commonPackages"
+	commonPackages=
+	for packageFile in $unfilteredCommonPackages; do
+		if is_in_list "$packageFile" "$systemPackages"; then
+			:
+		else
+			commonPackages="$commonPackages $packageFile"
+		fi
+	done
+
 	# additional packages for common
 	packageUrls=`$getPackageDependencies $repositories -- $systemPackages \
 		$commonPackages`