define AM_COND_IF if not yet defined (needed to build with automake 1.10)

Patch from Dave Goodell



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@12568 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/configure.in b/configure.in
index 69544b4..5b46244 100644
--- a/configure.in
+++ b/configure.in
@@ -616,6 +616,19 @@
 AM_CONDITIONAL(VGCONF_HAVE_PLATFORM_SEC,
                test x$VGCONF_PLATFORM_SEC_CAPS != x)
 
+dnl automake-1.10 does not have AM_COND_IF (added in 1.11), so we supply a
+dnl fallback definition
+dnl The macro is courtesy of Dave Hart:
+dnl   https://lists.gnu.org/archive/html/automake/2010-12/msg00045.html
+m4_ifndef([AM_COND_IF], [AC_DEFUN([AM_COND_IF], [
+if test -z "$$1_TRUE"; then :
+  m4_n([$2])[]dnl
+m4_ifval([$3],
+[else
+  $3
+])dnl
+fi[]dnl
+])])
 
 #----------------------------------------------------------------------------
 # Inner Valgrind?