Kbuild arm: LLVMLinux: Add Kbuild support for building arch arm with Clang

Protect more options for arm with cc-option so that we don't get errors when
using clang instead of gcc.  Add more or different options when using clang as
well.

Author: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Kbuild: LLVMLinux: Add Kbuild support for building kernel with Clang

Add support for for compiling with clang to Kbuild

Author: Behan Webster <behanw@converseincode.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>

Conflicts:
	Makefile