Fix some typos found by codespell

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
diff --git a/migration/ram.c b/migration/ram.c
index 3f05738..88fbffc 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1272,7 +1272,7 @@
 }
 
 /**
- * ram_save_host_page: Starting at *offset send pages upto the end
+ * ram_save_host_page: Starting at *offset send pages up to the end
  *                     of the current host page.  It's valid for the initial
  *                     offset to point into the middle of a host page
  *                     in which case the remainder of the hostpage is sent.