filter: use --switch=2 --readonly-tables gperf options

See 73ecb924 (Use --switch=2
--readonly-tables gperf options, 2014-04-13) for reasoning.

Change-Id: Ic63747a6cd982557cad8470ae775afa4b3d8d883

filter/CustomTarget_svg.mk

@@ -37,7 +37,7 @@ $(filter_GEN_svg_Tokens_hxx) : $(filter_GEN_svg_Tokens_gperf)
 $(filter_GEN_svg_Tokens_cxx) : $(filter_GEN_svg_Tokens_gperf)
 	$(call gb_Output_announce,$(subst $(WORKDIR)/,,$@),build,GPF,1)
 	$(call gb_Helper_abbreviate_dirs, \
-		 $(GPERF) --compare-strncmp -C -m 20  $(filter_GEN_svg_Tokens_gperf) \
+		 $(GPERF) --compare-strncmp -C -m 20 --switch=2 --readonly-tables $(filter_GEN_svg_Tokens_gperf) \
 			 | sed -e "s/(char\*)0/(char\*)0$(COMMA) 0/g" \
 			 > $(filter_GEN_svg_Tokens_cxx))