Move the HAVE_ARCH_* config options from src/arch/x86 to src/.

The options that keep track of whether there are arch versions of the standard
string functions shouldn't be in the arch/x86 directory since they apply to
all architectures. Move them into the higher level, shared Kconfig defaulting
to off. Then, in each applicable arch (currently all of them) they can be
selected to on.

Change-Id: I7ea64a583230fdc28773f17fd7cc23e0f0a5f3d6
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3760
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/Kconfig

@@ -236,6 +236,14 @@ if ARCH_ARMV7
 source src/arch/armv7/Kconfig
 endif
 
+config HAVE_ARCH_MEMSET
+	bool
+	default n
+
+config HAVE_ARCH_MEMCPY
+	bool
+	default n
+
 menu "Chipset"
 
 comment "CPU"