Makefile: remove no longer existing search paths

ArduinoAddons has been removed from Marlin, remove any references to it.
Replace HARDWARE_SRC and HARDWARE_DIR with its expanded equivalents.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>

Marlin/Makefile

 # Libraries, the "hardware variant" are for boards
 # that derives from that, and their source are present in
 # the main Marlin source directory
-ifeq ($(HARDWARE_VARIANT), $(filter $(HARDWARE_VARIANT),arduino Sanguino))
-HARDWARE_DIR = $(ARDUINO_INSTALL_DIR)/hardware
-else
-ifeq ($(shell [ $(ARDUINO_VERSION) -ge 100 ] && echo true), true)
-HARDWARE_DIR = ../ArduinoAddons/Arduino_1.x.x
-else
-HARDWARE_DIR = ../ArduinoAddons/Arduino_0.xx
-endif
-endif
-HARDWARE_SRC= $(HARDWARE_DIR)/arduino/avr/cores/arduino
 
 TARGET = $(notdir $(CURDIR))
 
 
 VPATH = .
 VPATH += $(BUILD_DIR)
-VPATH += $(HARDWARE_SRC)
-ifeq ($(HARDWARE_VARIANT), $(filter $(HARDWARE_VARIANT),arduino Teensy Sanguino))
-VPATH += $(HARDWARE_DIR)/marlin/avr/libraries/LiquidCrystal/src
-VPATH += $(HARDWARE_DIR)/marlin/avr/libraries/SPI
-VPATH += $(HARDWARE_DIR)/arduino/avr/libraries/SPI
-VPATH += $(HARDWARE_DIR)/arduino/avr/libraries/SPI/src
+VPATH += $(ARDUINO_INSTALL_DIR)/hardware/arduino/avr/cores/arduino
+
+VPATH += $(ARDUINO_INSTALL_DIR)/hardware/arduino/avr/libraries/SPI
+VPATH += $(ARDUINO_INSTALL_DIR)/hardware/arduino/avr/libraries/SPI/src
 VPATH += $(ARDUINO_INSTALL_DIR)/libraries/LiquidCrystal/src
 ifeq ($(LIQUID_TWI2), 1)
 VPATH += $(ARDUINO_INSTALL_DIR)/libraries/Wire
 VPATH += $(ARDUINO_INSTALL_DIR)/libraries/Wire
 VPATH += $(ARDUINO_INSTALL_DIR)/libraries/Wire/utility
 endif
-else
-VPATH += $(HARDWARE_DIR)/libraries/LiquidCrystal
-VPATH += $(HARDWARE_DIR)/libraries/SPI
-ifeq ($(LIQUID_TWI2), 1)
-VPATH += $(HARDWARE_DIR)/libraries/Wire
-VPATH += $(HARDWARE_DIR)/libraries/Wire/utility
-VPATH += $(HARDWARE_DIR)/libraries/LiquidTWI2
-endif
-ifeq ($(WIRE), 1)
-VPATH += $(HARDWARE_DIR)/libraries/Wire
-VPATH += $(HARDWARE_DIR)/libraries/Wire/utility
-endif
-endif
+
 ifeq ($(HARDWARE_VARIANT), arduino)
 HARDWARE_SUB_VARIANT ?= mega
-VPATH += $(ARDUINO_INSTALL_DIR)/hardware/arduino/variants/$(HARDWARE_SUB_VARIANT)
 VPATH += $(ARDUINO_INSTALL_DIR)/hardware/arduino/avr/variants/$(HARDWARE_SUB_VARIANT)
 else
 ifeq ($(HARDWARE_VARIANT), Sanguino)