The DEBUG_WRITERFILTER code should be a dbgutil thing

DEBUG_WRITERFILTER being on or off introduces binary incompatibility
between object files that implement and use those things, so it
shouldn't be changed without a full recompilation. Thus is matches
dbgutil.

Change-Id: Iec3c713ca7b299daf4b9cf1c978e49bf5ddf6886
Reviewed-on: https://gerrit.libreoffice.org/69438
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>

writerfilter/Library_writerfilter.mk

@@ -28,7 +28,7 @@ $(eval $(call gb_Library_use_sdk_api,writerfilter))
 $(eval $(call gb_Library_set_componentfile,writerfilter,writerfilter/util/writerfilter))
 
 $(eval $(call gb_Library_add_defs,writerfilter,\
-	$(if $(filter-out 0,$(gb_DEBUGLEVEL)), \
+	$(if $(ENABLE_DBGUTIL), \
 		-DDEBUG_WRITERFILTER \
 	) \
 ))

writerfilter/README

@@ -12,7 +12,7 @@ Import filter for docx and rtf.
 == Source contents ==
  * dmapper: the domain mapper, hiding UNO from the tokenizers, used by DOCX and RTF import
    * The incoming traffic of dmapper can be dumped into an XML file in /tmp in
-     debug builds, start soffice with the `SW_DEBUG_WRITERFILTER=1`
+     dbgutil builds, start soffice with the `SW_DEBUG_WRITERFILTER=1`
      environment variable if you want that.
  * filter: the UNO filter service implementations, invoked by UNO and calling
    the dmapper + one of the tokenizers