[gnome-calculator] trivial: use AM_CPPFLAGS, not INCLUDES

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 7a96edaf9eb6a129873dd316a40fe64495da5ffa
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Wed Feb 26 16:08:50 2014 -0600

    trivial: use AM_CPPFLAGS, not INCLUDES

 src/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 7c561d3..fc38cc6 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -3,7 +3,7 @@ noinst_PROGRAMS = test-number test-equation test-serializer
 
 TESTS = test-number test-equation test-serializer
 
-INCLUDES = \
+AM_CPPFLAGS = \
        -DUI_DIR=\""$(datadir)/gnome-calculator"\" \
        -DVERSION=\""$(VERSION)"\" \
        -DLOCALE_DIR=\""$(localedir)"\" \