kbuild: remove redundant target cleaning on failure

Since commit 9c2af1c737 ("kbuild: add .DELETE_ON_ERROR special
target"), the target file is automatically deleted on failure.

The boilerplate code

  ... || { rm -f $@; false; }

is unneeded.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

arch/x86/boot/compressed/Makefile

@@ -151,7 +151,7 @@ suffix-$(CONFIG_KERNEL_LZO) 	:= lzo
 suffix-$(CONFIG_KERNEL_LZ4) 	:= lz4
 
 quiet_cmd_mkpiggy = MKPIGGY $@
-      cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
+      cmd_mkpiggy = $(obj)/mkpiggy $< > $@
 
 targets += piggy.S
 $(obj)/piggy.S: $(obj)/vmlinux.bin.$(suffix-y) $(obj)/mkpiggy FORCE