kbuild: trivial documentation fixes

What is covered within this file is mainly information to authors

of modules. The author of an external module should supply

a makefile that hides most of the complexity, so one only has to type

'make' to build the module. A complete example will be present in

'make' to build the module. A complete example will be presented in

chapter 4, "Creating a kbuild file for an external module".

		make -C <path-to-kernel> M=`pwd`

	For the running kernel use:

		make -C /lib/modules/`uname -r`/build M=`pwd`

	For the above command to succeed, the kernel must have been

	To make sure the kernel contains the information required to

	build external modules the target 'modules_prepare' must be used.

	'module_prepare' exists solely as a simple way to prepare

	'modules_prepare' exists solely as a simple way to prepare

	a kernel source tree for building external modules.

	Note: modules_prepare will not build Module.symvers even if

	CONFIG_MODULEVERSIONING is set. Therefore a full kernel build

	CONFIG_MODVERSIONS is set. Therefore a full kernel build

	needs to be executed to make module versioning work.

--- 2.5 Building separate files for a module

Module.symvers contains a list of all exported symbols from a kernel build.

--- 7.1 Symbols fron the kernel (vmlinux + modules)

--- 7.1 Symbols from the kernel (vmlinux + modules)

	During a kernel build, a file named Module.symvers will be generated.

	Module.symvers contains all exported symbols from the kernel and