kinetis_ke: Switch to standard build variables

Instead of using ARM_ prefixed variables and an "arm" target,
use CROSS_COMPILE, AS, OBJCOPY. This requires to switch from ?= to =
to avoid the host assembler getting invoked.

This allows to handle kinetis_ke subdirectory like fm4 and xmc1xxx.

Change-Id: I7ea0bf119f6c4716f4d6002794004730af49eef4
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-on: http://openocd.zylin.com/3505
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

contrib/loaders/Makefile

@@ -5,13 +5,13 @@ all: arm
 common_dirs = \
 	checksum \
 	erase_check \
-	flash/kinetis_ke \
 	watchdog
 
 ARM_CROSS_COMPILE ?= arm-none-eabi-
 
 arm_dirs = \
 	flash/fm4 \
+	flash/kinetis_ke \
 	flash/xmc1xxx
 
 arm:

contrib/loaders/flash/kinetis_ke/Makefile

@@ -1,18 +1,18 @@
 BIN2C = ../../../../src/helper/bin2char.sh
 
-ARM_CROSS_COMPILE ?= arm-none-eabi-
-ARM_AS      ?= $(ARM_CROSS_COMPILE)as
-ARM_OBJCOPY ?= $(ARM_CROSS_COMPILE)objcopy
+CROSS_COMPILE ?= arm-none-eabi-
+AS      = $(CROSS_COMPILE)as
+OBJCOPY = $(CROSS_COMPILE)objcopy
 
-arm: kinetis_ke_flash.inc kinetis_ke_watchdog.inc
+all: kinetis_ke_flash.inc kinetis_ke_watchdog.inc
 
-kinetis_ke_%.elf: kinetis_ke_%.s
-	$(ARM_AS) $< -o $@
+%.elf: %.s
+	$(AS) $< -o $@
 
-kinetis_ke_%.bin: kinetis_ke_%.elf
-	$(ARM_OBJCOPY) -Obinary $< $@
+%.bin: %.elf
+	$(OBJCOPY) -Obinary $< $@
 
-kinetis_ke_%.inc: kinetis_ke_%.bin
+%.inc: %.bin
 	$(BIN2C) < $< > $@
 
 clean: