Configure: create missing intermediates for build directory.

Signed-off-by: Piotr Sikora <piotr@cloudflare.com>

auto/configure

diff --git a/auto/configure b/auto/configure
index 617d992..ceff15e 100755
--- a/auto/configure
+++ b/auto/configure
@@ -11,7 +11,7 @@
 . auto/init
 . auto/sources
 
-test -d $NGX_OBJS || mkdir $NGX_OBJS
+test -d $NGX_OBJS || mkdir -p $NGX_OBJS
 
 echo > $NGX_AUTO_HEADERS_H
 echo > $NGX_AUTOCONF_ERR