configure: work around bug in ash shell

The ash 'test' builtin misbehaves if the first operand of a binary
operator looks like a unary operator.

Signed-off-by: Mans Rullgard <mans@mansr.com>

diff --git a/configure b/configure
index 26cd7ea..22becbf 100755 (executable)
--- a/configure
+++ b/configure
@@ -593,7 +593,7 @@ print_config(){
 }
 
 print_enabled(){
-    test "$1" = -n && end=" " && shift || end="\n"
+    test x"$1" = x-n && end=" " && shift || end="\n"
     suf=$1
     shift
     for v; do