ENABLE_CORETEXT: Harmonize ENABLE_* variable to TRUE/<nothing>

Change-Id: I39153ee042b171f7cd1ffa6b50c490d2c9fa33cb
Reviewed-on: https://gerrit.libreoffice.org/5685Reviewed-by: Fridrich Strba <fridrich@documentfoundation.org>
Tested-by: Fridrich Strba <fridrich@documentfoundation.org>

configure.ac

@@ -11234,12 +11234,12 @@ AC_SUBST(WITH_HELPPACK_INTEGRATION)
 dnl ===================================================================
 dnl Test whether to use CoreText framework
 dnl ===================================================================
-ENABLE_CORETEXT=NO
+ENABLE_CORETEXT=
 if test "$_os" = "Darwin"; then
     AC_MSG_CHECKING([whether to use CoreText framework])
     if test "$enable_coretext" != no -o "$BITNESS_OVERRIDE" = 64; then
         AC_MSG_RESULT([yes])
-        ENABLE_CORETEXT=YES
+        ENABLE_CORETEXT=TRUE
     else
         AC_MSG_RESULT([no])
     fi

vcl/Library_vcl.mk

@@ -356,7 +356,7 @@ $(eval $(call gb_Library_add_defs,vcl,\
 	-DMACOSX_BUNDLE_IDENTIFIER=\"$(MACOSX_BUNDLE_IDENTIFIER)\" \
 ))
 
-ifeq ($(ENABLE_CORETEXT),YES)
+ifeq ($(ENABLE_CORETEXT),TRUE)
 
 $(eval $(call gb_Library_add_defs,vcl,\
     -DENABLE_CORETEXT \