Rename config.{h, mak} config-target.{h, mak}

Add config.h file that includes config-target.h and config-host.h

Patchworks-ID: 35193
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/.gitignore b/.gitignore
index ac2368b..7e6d844 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 config-host.*
+config-target.*
 i386
 *-softmmu
 *-darwin-user