Move the Configure generated header files to the top build.info

This turns these headers into build file generated ones.

Reviewed-by: Rich Salz <rsalz@openssl.org>

build.info

diff --git a/build.info b/build.info
index 6bc70c6..6f057cd 100644
--- a/build.info
+++ b/build.info
@@ -6,6 +6,18 @@
 INCLUDE[libssl]="{- rel2abs(catdir($builddir,"include")) -}" . include
 DEPEND[libssl]=libcrypto
 
+# Empty DEPEND "indices" means the dependencies are expected to be built
+# unconditionally before anything else.
+DEPEND[]=include/openssl/opensslconf.h crypto/include/internal/bn_conf.h \
+         crypto/include/internal/dso_conf.h
+DEPEND[include/openssl/opensslconf.h]=configdata.pm
+GENERATE[include/openssl/opensslconf.h]=include/openssl/opensslconf.h.in
+DEPEND[crypto/include/internal/bn_conf.h]=configdata.pm
+GENERATE[crypto/include/internal/bn_conf.h]=crypto/include/internal/bn_conf.h.in
+DEPEND[crypto/include/internal/dso_conf.h]=configdata.pm
+GENERATE[crypto/include/internal/dso_conf.h]=crypto/include/internal/dso_conf.h.in
+
+
 IF[{- $config{target} =~ /^Cygwin/ -}]
  SHARED_NAME[libcrypto]=cygcrypto-{- $config{shlib_major}.".".$config{shlib_minor} -}
  SHARED_NAME[libssl]=cygssl-{- $config{shlib_major}.".".$config{shlib_minor} -}