Snap: use ARCH instead of PLATFORM (diff snap concept)

Author: ysbaddaden

snapcraft/Makefile

@@ -1,11 +1,11 @@
 OUTPUT_DIR = build
 CRYSTAL_TARBALL =
-PLATFORM =
+ARCH =
 
 .PHONY: all
 all: snap/snapcraft.yaml
 	mkdir -p $(OUTPUT_DIR)
-	snapcraft --build-for=$(PLATFORM)
+	snapcraft --build-for=$(ARCH)
 	mv *.snap $(OUTPUT_DIR)
 
 .PHONY: snap/snapcraft.yaml