kbuild: make cc-version available in kbuild files

Move $(CC) support functions to Kbuild.include so they are available
in the kbuild files.
In addition the following was done:
	o as-option documented in Documentation/kbuild/makefiles.txt
	o Moved documentation to new section to match
	  new scope of functions
	o added cc-ifversion used to conditionally select a text string
	  dependent on actual $(CC) version
	o documented cc-ifversion
	o change so Kbuild.include is read before the kbuild file

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index c33e62bde6b0..2737765f2fb4 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -10,11 +10,12 @@ __build:
 # Read .config if it exist, otherwise ignore
 -include .config
 
+include scripts/Kbuild.include
+
 # The filename Kbuild has precedence over Makefile
 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
 include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)
 
-include scripts/Kbuild.include
 include scripts/Makefile.lib
 
 ifdef host-progs