configs: correctly terminate loop

The switch_to_toplevel() function in process_configs.sh contains a buggy
loop. It tests whether $path is empty but should test whether $path
equals "/". (It repeatedly calls dirname on pwd's output, and since pwd
will return an absolute path this will, eventually, return "/" forever.)
So let's test for "/" here.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>

configs/process_configs.sh

@@ -14,7 +14,7 @@ die()
 switch_to_toplevel()
 {
 	path="$(pwd)"
-	while test -n "$path"
+	while test "$path" != "/"
 	do
 		test -e $path/MAINTAINERS && \
 		test -d $path/drivers && \
@@ -23,7 +23,7 @@ switch_to_toplevel()
 		path="$(dirname $path)"
 	done
 
-	test -n "$path"  || die "Can't find toplevel"
+	test "$path" != "/" || die "Can't find toplevel"
 	echo "$path"
 }