libroot_x86: use the generic memset/memcpy when x86_64 is the primary arch.

the standard x86 implementation uses the commpage, which is difficult to setup. we could
also use the C++11 version instead.

Change-Id: I4be7e3466082ff2c91bc32bef377a664ce65f3fc

* Moved the arch specific stuff in src/system/kernel/lib into arch/...
subdirectories. Also moved the x86 kernel arch_string.S there.
* Moved memcpy.c from src/system/libroot/posix/string into the
arch/generic subdirectory.
* Dealt with the consequences of moving things around. Affected are also
the boot loader and runtime loader builds.

Adjust the m68k and ppc parts, too, but only the x86 build is tested.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27947 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Moved the arch specific stuff in src/system/kernel/lib into arch/...
subdirectories. Also moved the x86 kernel arch_string.S there.
* Moved memcpy.c from src/system/libroot/posix/string into the
arch/generic subdirectory.
* Dealt with the consequences of moving things around. Affected are also
the boot loader and runtime loader builds.

Adjust the m68k and ppc parts, too, but only the x86 build is tested.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27947 a95241bf-73f2-0310-859d-f6bbb57e9c96