The capi engine uses stdio, so don't build it when configuring 'no-stdio'

Reviewed-by: Rich Salz <rsalz@openssl.org>
diff --git a/Configure b/Configure
index d4f67ab..bf5b2c6 100755
--- a/Configure
+++ b/Configure
@@ -437,7 +437,7 @@
     # no-autoalginit is only useful when building non-shared
     "autoalginit"       => [ "shared", "apps" ],
 
-    "stdio"             => [ "apps" ],
+    "stdio"             => [ "apps", "capieng" ],
     "apps"              => [ "tests" ],
     "comp"		=> [ "zlib" ],
     sub { !$disabled{"unit-test"} } => [ "heartbeats" ],