Move the inline assembly into its own file

Clang was having trouble handling some of the assembly instructions when
they were declared in the C file

Remove -u __vsyscall_ptr build flag setting

This was required to use libsel4muslcsys but depending on the library
will create this flag automatically.

sel4test-tests: Use arm arch files on RISC-V

Instead of duplicating the implementation, we use the Arm one. It is
expected that eventually these arch functions become non-arch.

sel4test: explicitly link sel4_autoconf

since the global conf lib is going be removed, we need to explicitly
linke each project with sel4_autoconf and other config libs
this commit also removed a bunch of unused includes as well as
HAVE_AUTOCONF ifdef checking.

sel4test: remove autoconf.h from sel4test

this commit removes autoconf.h generation from sel4test and
append '#include <sel4test/gen_config.h>' after each
'#include <autoconf.h>' since autoconf.h is only the for the
kernel config now. This is a temporarily solution, since we
currently don't have a way to tell which header files each file
is trying to include when it includes 'autoconf.h'

sel4test-tests: depend on sel4serialserver_tests

This is where the serialserver tests now live.

trivial: style changed files

sel4test-tests: request serial caps from driver

Since we can only allocate individual frame capabilities once, currently
sel4test passes the serial frame into test processes explicitly.

We remove this explicit mechanism, and make sel4test-tests send a RPC
message to the test driver to request these frames when they're
allocated.

Depend on sel4runtime.

Avoid redundantly declaring src directory as include path

For source relative includes with "" the src directory will already be checked for headers
and so it does not need to be explicitly added as an include path

Add CMake configuration files

Add CMake build rules for building the two sel4test applications