kbuild: correct and clarify versioning info in Makefile

	$(Q)$(MAKE) $(build)=$@

# Build the kernel release string

# The KERNELRELEASE is stored in a file named include/config/kernel.release

# to be used when executing for example make install or make modules_install

#

# Take the contents of any files called localversion* and the config

# variable CONFIG_LOCALVERSION and append them to KERNELRELEASE.

# LOCALVERSION from the command line override all of this

# The KERNELRELEASE value built here is stored in the file

# include/config/kernel.release, and is used when executing several

# make targets, such as "make install" or "make modules_install."

#

# The eventual kernel release string consists of the following fields,

# shown in a hierarchical format to show how smaller parts are concatenated

# to form the larger and final value, with values coming from places like

# the Makefile, kernel config options, make command line options and/or

# SCM tag information.

#

#	$(KERNELVERSION)

#	  $(VERSION)			eg, 2

#	  $(PATCHLEVEL)			eg, 6

#	  $(SUBLEVEL)			eg, 18

#	  $(EXTRAVERSION)		eg, -rc6

#	$(localver-full)

#	  $(localver)

#	    localversion*		(all localversion* files)

#	    $(CONFIG_LOCALVERSION)	(from kernel config setting)

#	  $(localver-auto)		(only if CONFIG_LOCALVERSION_AUTO is set)

#	    ./scripts/setlocalversion	(SCM tag, if one exists)

#	    $(LOCALVERSION)		(from make command line if provided)

#

#  Note how the final $(localver-auto) string is included *only* if the

# kernel config option CONFIG_LOCALVERSION_AUTO is selected.  Also, at the

# moment, only git is supported but other SCMs can edit the script

# scripts/setlocalversion and add the appropriate checks as needed.

nullstring :=

space      := $(nullstring) # end of line