[m-rev.] diff: Conform to renaming of configure.in to configure.ac.

[Peter Wang]

Branches: main, release
---

commit 81060340ee9480ce7936d44e09b257cf9eff5395
Author: Peter Wang <novalazy at gmail.com>
Date:   Tue Feb 12 11:15:10 2013 +1100

    Conform to renaming of configure.in to configure.ac.
    
    tools/configure_mingw_cross:
    	Check for configure.ac instead of configure.in as it was
    	renamed.

diff --git a/tools/configure_mingw_cross b/tools/configure_mingw_cross
index 614cbd6..3f43e69 100755
--- a/tools/configure_mingw_cross
+++ b/tools/configure_mingw_cross
@@ -41,12 +41,12 @@ else
     exit 2
 fi
 
-if test configure -ot configure.in
+if test configure -ot configure.ac
 then
     aclocal -I m4 && autoconf
 fi
 
-if ! test -f configure.in
+if ! test -f configure.ac
 then
     echo "You need to run this script at the top of the Mercury tree."
     exit 3