sane-backends: Make sane-backends.pc available

Signed-off-by: Sebastian Muszynski <basti@linkt.de>

utils/sane-backends/Makefile

@@ -216,6 +216,8 @@ define Build/InstallDev
 	$(CP) $(PKG_INSTALL_DIR)/usr/include/sane $(1)/usr/include/
 	$(INSTALL_DIR) $(1)/usr/lib
 	$(CP) $(PKG_INSTALL_DIR)/usr/lib/libsane.{a,so*} $(1)/usr/lib/
+	$(INSTALL_DIR) $(1)/usr/lib/pkgconfig
+	$(CP) $(PKG_BUILD_DIR)/tools/sane-backends.pc $(1)/usr/lib/pkgconfig/
 endef
 
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