tests: arch: add a test case for testing arch_nop() interface

Add a test case to test arch interface arch_nop(), the main focus here
is for coverage of the code. arch_nop() is a special implementation
and it will behave differently on different platforms. By the way, this
also measures how many cycles it spends for platforms that support it.

Signed-off-by: Enjia Mai <enjiax.mai@intel.com>