kbuild: fix tags generation of config symbols

commit 4f628248a5 aka "kbuild: reintroduce
ALLSOURCE_ARCHS support for tags/cscope" breaks tags generation for
Kconfig symbols.

Steps to reproduce:

	make tags
	vi -t PROC_FS

It should jump to 'config PROC_FS' line.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Tested-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/tags.sh

@@ -76,7 +76,10 @@ all_sources()
 
 all_kconfigs()
 {
-	find_sources $ALLSOURCE_ARCHS 'Kconfig*'
+	for arch in $ALLSOURCE_ARCHS; do
+		find_sources $arch 'Kconfig*'
+	done
+	find_other_sources 'Kconfig*'
 }
 
 all_defconfigs()