treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

arch/csky/Kconfig

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 config CSKY
 	def_bool y
 	select ARCH_32BIT_OFF_T

arch/csky/Kconfig.debug

@@ -1 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
 # dummy file, do not delete

arch/csky/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 OBJCOPYFLAGS		:=-O binary
 GZFLAGS			:=-9
 KBUILD_DEFCONFIG	:= defconfig

arch/csky/abiv1/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_CPU_NEED_SOFTALIGN)	+= alignment.o
 obj-y					+= bswapdi.o
 obj-y					+= bswapsi.o

arch/csky/abiv2/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 obj-y				+= cacheflush.o
 obj-$(CONFIG_CPU_HAS_FPU)	+= fpu.o
 obj-y				+= memcmp.o

arch/csky/boot/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 targets := Image zImage uImage
 targets += $(dtb-y)
 

arch/csky/boot/dts/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 dtstree	:= $(srctree)/$(src)
 
 dtb-y := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))

arch/csky/kernel/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 extra-y := head.o vmlinux.lds
 
 obj-y += entry.o atomic.o signal.o traps.o irq.o time.o vdso.o

arch/csky/lib/Makefile

@@ -1 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
 lib-y  := usercopy.o delay.o

arch/csky/mm/Makefile

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 ifeq ($(CONFIG_CPU_HAS_CACHEV2),y)
 obj-y +=			cachev2.o
 else