do not install merged libraries

Since scp2 / make_installer ignores undefined ids, we can just
filter-out merged autoinstalled libraries and we are done :-)

Change-Id: I5ab63604d54a5a36caccf003a20112e2b47b79da

solenv/gbuild/Helper.mk

@@ -183,7 +183,7 @@ $$(eval $$(call gb_Output_error,$(2) is not a valid install module for libraries
 endif
 $(call gb_Helper_register_libraries,$(1),$(3))
 
-gb_Library_MODULE_$(2) += $(3)
+gb_Library_MODULE_$(2) += $(filter-out $(gb_MERGEDLIBS) $(gb_URELIBS),$(3))
 
 endef