msi: Constify a variable

[Andrew Talbot]

Changelog:
    msi: Constify a variable.

diff -urN a/dlls/msi/format.c b/dlls/msi/format.c
--- a/dlls/msi/format.c	2007-05-25 23:23:57.000000000 +0100
+++ b/dlls/msi/format.c	2007-06-11 22:52:11.000000000 +0100
@@ -45,7 +45,7 @@
                                      BOOL* in_group);
 
 
-static LPWSTR build_default_format(MSIRECORD* record)
+static LPWSTR build_default_format(const MSIRECORD* record)
 {
     int i;  
     int count;