exec: introduce target_words_bigendian() helper

We currently have a virtio_is_big_endian() helper that provides the target
endianness to the virtio code. As of today, the helper returns a fixed
compile-time value. Of course, this will have to change if we want to
support target endianness changes at run-time.

Let's move the TARGET_WORDS_BIGENDIAN bits out to a new helper and have
virtio_is_big_endian() implemented on top of it.

This patch doesn't change any functionality.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/exec.c b/exec.c
index a94c583..18d6c35 100644
--- a/exec.c
+++ b/exec.c
@@ -2759,14 +2759,12 @@
 }
 #endif
 
-#if !defined(CONFIG_USER_ONLY)
-
 /*
  * A helper function for the _utterly broken_ virtio device model to find out if
  * it's running on a big endian machine. Don't do this at home kids!
  */
-bool virtio_is_big_endian(void);
-bool virtio_is_big_endian(void)
+bool target_words_bigendian(void);
+bool target_words_bigendian(void)
 {
 #if defined(TARGET_WORDS_BIGENDIAN)
     return true;
@@ -2775,8 +2773,6 @@
 #endif
 }
 
-#endif
-
 #ifndef CONFIG_USER_ONLY
 bool cpu_physical_memory_is_io(hwaddr phys_addr)
 {