tools/Makefile: remove stray whitespace from APP_DIR (#3240)

Author: sorki

tools/Makefile

@@ -7,7 +7,7 @@ LUASOURCE ?= ../local/lua
 FLASHSIZE ?= 4mb 32mb 8mb
 FLASH_SW = -S
 SUBDIRS =
-APP_DIR = ../app 
+APP_DIR = ../app
 OBJDUMP = $(or $(shell which objdump),xtensa-lx106-elf-objdump)
 
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