kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Kbuild

@@ -7,7 +7,7 @@
 
 bounds-file := include/generated/bounds.h
 
-always  := $(bounds-file)
+always-y := $(bounds-file)
 targets := kernel/bounds.s
 
 $(bounds-file): kernel/bounds.s FORCE
@@ -28,7 +28,7 @@ $(timeconst-file): kernel/time/timeconst.bc FORCE
 
 offsets-file := include/generated/asm-offsets.h
 
-always  += $(offsets-file)
+always-y += $(offsets-file)
 targets += arch/$(SRCARCH)/kernel/asm-offsets.s
 
 arch/$(SRCARCH)/kernel/asm-offsets.s: $(timeconst-file) $(bounds-file)
@@ -39,7 +39,7 @@ $(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
 #####
 # Check for missing system calls
 
-always += missing-syscalls
+always-y += missing-syscalls
 
 quiet_cmd_syscalls = CALL    $<
       cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)
@@ -50,7 +50,7 @@ missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
 #####
 # Check atomic headers are up-to-date
 
-always += old-atomics
+always-y += old-atomics
 
 quiet_cmd_atomics = CALL    $<
       cmd_atomics = $(CONFIG_SHELL) $<