Add ICU_CFLAGS to global CPPFLAGS

The original code only added ICU_CFLAGS to the backend build.  But it is
also needed for building external modules that include pg_locale.h.  So
add it to the global CPPFLAGS.  (This is only relevant if ICU is not in
a compiler default path, so it apparently hasn't bitten many.)

src/Makefile.global.in

@@ -232,6 +232,8 @@ PTHREAD_LIBS		= @PTHREAD_LIBS@
 CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
 
+override CPPFLAGS := $(CPPFLAGS) $(ICU_CFLAGS)
+
 ifdef PGXS
 override CPPFLAGS := -I$(includedir_server) -I$(includedir_internal) $(CPPFLAGS)
 else # not PGXS

src/backend/common.mk

@@ -8,8 +8,6 @@
 # this directory and SUBDIRS to subdirectories containing more things
 # to build.
 
-override CPPFLAGS := $(CPPFLAGS) $(ICU_CFLAGS)
-
 ifdef PARTIAL_LINKING
 # old style: linking using SUBSYS.o
 subsysfilename = SUBSYS.o

src/backend/snowball/Makefile

@@ -14,8 +14,7 @@ top_builddir = ../../..
 include $(top_builddir)/src/Makefile.global
 
 override CPPFLAGS := -I$(top_srcdir)/src/include/snowball \
-	-I$(top_srcdir)/src/include/snowball/libstemmer $(CPPFLAGS) \
-	$(ICU_CFLAGS)
+	-I$(top_srcdir)/src/include/snowball/libstemmer $(CPPFLAGS)
 
 OBJS= $(WIN32RES) dict_snowball.o api.o utilities.o \
 	stem_ISO_8859_1_danish.o \