build: formatting fixes for per-provide ABI_VERSION suffixes

- Filter out potential duplicates with the package name
   (e.g. when renaming libfoo1 w/ ABI_VERSION:=1 to libfoo)
 - Use the GetABISuffix macro to properly separate the suffix
   with a dash in case the basename ends with a number

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

include/package-ipkg.mk

@@ -162,7 +162,7 @@ Package: $(1)$$(ABIV_$(1))
 Version: $(VERSION)
 $$(call addfield,Depends,$$(Package/$(1)/DEPENDS)
 )$$(call addfield,Conflicts,$$(call mergelist,$(CONFLICTS))
-)$$(call addfield,Provides,$$(call mergelist,$(PROVIDES)$$(if $$(ABIV_$(1)), $(1) $(foreach provide,$(PROVIDES),$(provide)$$(ABIV_$(1)))))
+)$$(call addfield,Provides,$$(call mergelist,$$(filter-out $(1)$$(ABIV_$(1)),$(PROVIDES)$$(if $$(ABIV_$(1)), $(1) $(foreach provide,$(PROVIDES),$(provide)$$(call GetABISuffix,$(provide))))))
 )$$(call addfield,Alternatives,$$(call mergelist,$(ALTERNATIVES))
 )$$(call addfield,Source,$(SOURCE)
 )$$(call addfield,SourceName,$(1)