.gitignore: move *.dtb and *.dtb.S patterns to the top-level .gitignore

Most of DT files are compiled under arch/*/boot/dts/, but we have some
other directories, like drivers/of/unittest-data/.  We often miss to
add gitignore patterns per directory.  Since there are no source files
that end with .dtb or .dtb.S, we can ignore the patterns globally.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Rob Herring <robh@kernel.org>

.gitignore

@@ -14,6 +14,8 @@
 *.bin
 *.bz2
 *.c.[012]*.*
+*.dtb
+*.dtb.S
 *.dwo
 *.elf
 *.gcno

arch/arc/boot/.gitignore

-*.dtb*
 uImage

arch/arm/boot/.gitignore

@@ -3,4 +3,3 @@ zImage
 xipImage
 bootpImage
 uImage
-*.dtb

arch/arm64/boot/dts/.gitignore

-*.dtb

arch/metag/boot/.gitignore

 vmlinux*
 uImage*
 ramdisk.*
-*.dtb*

arch/microblaze/boot/.gitignore

-*.dtb
 linux.bin*
 simpleImage.*

arch/mips/boot/.gitignore

@@ -5,4 +5,3 @@ zImage
 zImage.tmp
 calc_vmlinuz_load_addr
 uImage
-*.dtb

arch/nios2/boot/.gitignore

-*.dtb
 vmImage

arch/powerpc/boot/.gitignore

@@ -18,7 +18,6 @@ otheros.bld
 uImage
 cuImage.*
 dtbImage.*
-*.dtb
 treeImage.*
 vmlinux.strip
 zImage

arch/xtensa/boot/.gitignore

 uImage
 zImage.redboot
-*.dtb

drivers/of/unittest-data/.gitignore

-testcases.dtb
-testcases.dtb.S