kbuild: rename arg-check to cmd-check

I prefer 'cmd-check' for consistency.

We have 'echo-cmd', 'cmd', 'cmd_and_fixdep', etc. in this file.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

scripts/Kbuild.include

@@ -207,12 +207,12 @@ objectify = $(foreach o,$(1),$(if $(filter /%,$(o)),$(o),$(obj)/$(o)))
 # See Documentation/kbuild/makefiles.txt for more info
 
 ifneq ($(KBUILD_NOCMDDEP),1)
-# Check if both arguments are the same including their order. Result is empty
+# Check if both commands are the same including their order. Result is empty
 # string if equal. User may override this check using make KBUILD_NOCMDDEP=1
-arg-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
+cmd-check = $(filter-out $(subst $(space),$(space_escape),$(strip $(cmd_$@))), \
                          $(subst $(space),$(space_escape),$(strip $(cmd_$1))))
 else
-arg-check = $(if $(strip $(cmd_$@)),,1)
+cmd-check = $(if $(strip $(cmd_$@)),,1)
 endif
 
 # Replace >$< with >$$< to preserve $ when reloading the .cmd file
@@ -228,12 +228,12 @@ make-cmd = $(call escsq,$(subst $(pound),$$(pound),$(subst $$,$$$$,$(cmd_$(1))))
 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
 
 # Execute command if command has changed or prerequisite(s) are updated.
-if_changed = $(if $(strip $(any-prereq) $(arg-check)),                       \
+if_changed = $(if $(strip $(any-prereq) $(cmd-check)),                       \
 	$(cmd);                                                              \
 	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
 
 # Execute the command and also postprocess generated .d dependencies file.
-if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),$(cmd_and_fixdep),@:)
+if_changed_dep = $(if $(strip $(any-prereq) $(cmd-check)),$(cmd_and_fixdep),@:)
 
 cmd_and_fixdep =                                                             \
 	$(cmd);                                                              \
@@ -243,7 +243,7 @@ cmd_and_fixdep =                                                             \
 # Usage: $(call if_changed_rule,foo)
 # Will check if $(cmd_foo) or any of the prerequisites changed,
 # and if so will execute $(rule_foo).
-if_changed_rule = $(if $(strip $(any-prereq) $(arg-check)),$(rule_$(1)),@:)
+if_changed_rule = $(if $(strip $(any-prereq) $(cmd-check)),$(rule_$(1)),@:)
 
 ###
 # why - tell why a target got built
@@ -269,7 +269,7 @@ why =                                                                        \
     $(if $(filter $@, $(PHONY)),- due to target is PHONY,                    \
         $(if $(wildcard $@),                                                 \
             $(if $(strip $(any-prereq)),- due to: $(any-prereq),             \
-                $(if $(arg-check),                                           \
+                $(if $(cmd-check),                                           \
                     $(if $(cmd_$@),- due to command line change,             \
                         $(if $(filter $@, $(targets)),                       \
                             - due to missing .cmd file,                      \