Merge pull request #4180 from michael-dev/features/libpq-pkgconfig-files

postgresql: InstallDev pkg-config files for libpq

libs/postgresql/Makefile

@@ -238,6 +238,8 @@ define Build/InstallDev
 	$(CP) $(PKG_INSTALL_DIR)/usr/include/postgresql $(1)/usr/include/
 	$(INSTALL_DIR) $(1)/usr/lib
 	$(CP) $(PKG_INSTALL_DIR)/usr/lib/libpq.{a,so*} $(1)/usr/lib/
+	$(INSTALL_DIR) $(1)/usr/lib/pkgconfig
+	$(CP) $(PKG_INSTALL_DIR)/usr/lib/pkgconfig/libpq.pc $(1)/usr/lib/pkgconfig/
 endef
 
 $(eval $(call HostBuild))