Check HAVE_RADEON only after checking for atomic operations.

Fixes problem that libdrm_radeon was disabled in Makefile even when configure
claimed that radeon was enabled.

Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
diff --git a/configure.ac b/configure.ac
index 0f15f7e..6ef3c61 100644
--- a/configure.ac
+++ b/configure.ac
@@ -158,8 +158,6 @@
 	AC_DEFINE(HAVE_NOUVEAU, 1, [Have nouveau (nvidia) support])
 fi
 
-AM_CONDITIONAL(HAVE_RADEON, [test "x$RADEON" = xyes])
-
 PKG_CHECK_MODULES(CAIRO, cairo, [HAVE_CAIRO=yes], [HAVE_CAIRO=no])
 if test "x$HAVE_CAIRO" = xyes; then
 	AC_DEFINE(HAVE_CAIRO, 1, [Have cairo support])
@@ -234,6 +232,7 @@
 fi
 
 AM_CONDITIONAL(HAVE_INTEL, [test "x$INTEL" != "xno"])
+AM_CONDITIONAL(HAVE_RADEON, [test "x$RADEON" != "xno"])
 
 AC_ARG_WITH([kernel-source],
             [AS_HELP_STRING([--with-kernel-source],