Fix IRIX testsuite debugging failures: $0 in functions.

[Ralf Wildenhues]

Applied and pushed.  The tests
  ./testsuite -k debugging

failed, as then ./run script tried to execute
at_func_create_debugging_script rather than ./micro-suite.

Cheers,
Ralf

    * lib/autotest/general.m4 (AT_INIT) <at_func_create_debugging_script>:
    Do not use $0 inside a function, as IRIX sh will set that to the
    function name rather than the script invocation name.

diff --git a/lib/autotest/general.m4 b/lib/autotest/general.m4
index 7a6ccfe..5e42df9 100644
--- a/lib/autotest/general.m4
+++ b/lib/autotest/general.m4
@@ -322,7 +322,7 @@ at_func_create_debugging_script ()
     echo 'test "${ZSH_VERSION+set}" = set dnl
 && alias -g '\''${1+"address@hidden"}'\''='\''"address@hidden"'\'''
     AS_ECHO(["cd '$at_dir'"])
-    AS_ECHO(["exec \${CONFIG_SHELL-$SHELL} $[0] -v -d ]dnl
+    AS_ECHO(["exec \${CONFIG_SHELL-$SHELL} $at_myself -v -d ]dnl
 [$at_debug_args $at_group \${1+\"address@hidden"}"])
     echo 'exit 1'
   } >$at_group_dir/run