Use echo instead of printf in __wasi_snapshot.h generation

Makefile

@@ -775,10 +775,10 @@ $(SYSROOT_INC)/bits/alltypes.h: $(LIBC_TOP_HALF_MUSL_DIR)/tools/mkalltypes.sed $
 $(SYSROOT_INC)/__wasi_snapshot.h:
 	mkdir -p "$(SYSROOT_INC)"
 ifeq ($(WASI_SNAPSHOT), p2)
-	printf '#ifndef __wasilibc_use_wasip2\n#define __wasilibc_use_wasip2\n#endif\n' \
+	echo '#ifndef __wasilibc_use_wasip2\n#define __wasilibc_use_wasip2\n#endif\n' \
 		> "$(SYSROOT_INC)/__wasi_snapshot.h"
 else
-	printf '/* This file is (practically) empty by default.  The Makefile will replace it\n   with a non-empty version that defines `__wasilibc_use_wasip2` if targeting\n   `wasm32-wasip2`.\n */\n\n' \
+	echo '/* This file is (practically) empty by default.  The Makefile will replace it\n   with a non-empty version that defines `__wasilibc_use_wasip2` if targeting\n   `wasm32-wasip2`.\n */\n\n' \
 		> "$(SYSROOT_INC)/__wasi_snapshot.h"
 endif