Use CPPFLAGS in mod_yaml

src/mod/languages/mod_yaml/Makefile.am

@@ -7,7 +7,8 @@ LIBYAML_A=$(YAMLBUILDLIB)/src/.libs/libyaml.a
 
 mod_LTLIBRARIES = mod_yaml.la
 mod_yaml_la_SOURCES  = mod_yaml.c
-mod_yaml_la_CFLAGS   = $(AM_CFLAGS) -I$(YAMLLIB)/include
+mod_yaml_la_CFLAGS   = $(AM_CFLAGS)
+mod_yaml_la_CPPFLAGS = $(AM_CPPFLAGS) -I$(YAMLLIB)/include
 mod_yaml_la_LIBADD   = $(switch_builddir)/libfreeswitch.la $(LIBYAML_A)
 mod_yaml_la_LDFLAGS  = -avoid-version -module -no-undefined -shared