memory: add big endian support to access_with_adjusted_size

This will be used to split 8-byte access down to two four-byte accesses.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

memory.c

@@ -362,8 +362,12 @@ static void access_with_adjusted_size(hwaddr addr,
     access_size = MAX(MIN(size, access_size_max), access_size_min);
     access_mask = -1ULL >> (64 - access_size * 8);
     for (i = 0; i < size; i += access_size) {
-        /* FIXME: big-endian support */
+#ifdef TARGET_WORDS_BIGENDIAN
+        access(opaque, addr + i, value, access_size,
+               (size - access_size - i) * 8, access_mask);
+#else
         access(opaque, addr + i, value, access_size, i * 8, access_mask);
+#endif
     }
 }