ARM: 9291/1: decompressor: simplify the path to the top vmlinux

With commit 8debed3e ("kbuild: export top-level LDFLAGS_vmlinux
only to scripts/Makefile.vmlinux") applied, we no longer see the error
message while building the ARM zImage, but we do not have a good reason
to complicate the file path either.

'$(obj)/../../../../vmlinux' is canonicalized to 'vmlinux'.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

arch/arm/boot/compressed/Makefile

@@ -107,7 +107,7 @@ ccflags-remove-$(CONFIG_FUNCTION_TRACER) += -pg
 asflags-y := -DZIMAGE
 
 # Supply kernel BSS size to the decompressor via a linker symbol.
-KBSS_SZ = $(shell echo $$(($$($(NM) $(obj)/../../../../vmlinux | \
+KBSS_SZ = $(shell echo $$(($$($(NM) vmlinux | \
 		sed -n -e 's/^\([^ ]*\) [ABD] __bss_start$$/-0x\1/p' \
 		       -e 's/^\([^ ]*\) [ABD] __bss_stop$$/+0x\1/p') )) )
 LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ)