configure.ac: fix check for jimtcl submodule

The file configure.ac checks if jimtcl submodule is present by
looking for the file jimtcl/configure.ac .
But jimtcl has switched to its own build system in 2011 and thus
dropped configure.ac . This cause a build issue on OpenOCD that
was incorrectly fixed by adding a dummy configure.ac in jimtcl.

Fix OpenOCD configure.ac to look for the correct file
jimtcl/configure .
After this fix, another fix would be proposed to jimtcl to drop
its useless dummy file configure.ac .

Change-Id: I705f72d83e374c8dd700baaa0c0bbe041f153605
Signed-off-by: Antonio Borneo <[email protected]>
Reported-by: Paul Fertser <[email protected]>
Reviewed-on: https://review.openocd.org/c/openocd/+/7437
Tested-by: jenkins
Reviewed-by: Paul Fertser <[email protected]>

Author: borneoa

configure.ac

@@ -574,7 +574,7 @@ AS_IF([test "x$enable_buspirate" != "xno"], [
 ])
 
 AS_IF([test "x$use_internal_jimtcl" = "xyes"], [
-  AS_IF([test -f "$srcdir/jimtcl/configure.ac"], [
+  AS_IF([test -f "$srcdir/jimtcl/configure"], [
     AS_IF([test "x$use_internal_jimtcl_maintainer" = "xyes"], [
       jimtcl_config_options="--disable-install-jim --with-ext=json --maintainer"
     ], [