ARM: Stop using SEL4_ARCH for selective compilation for armv source files

SELFOUR-448 Benchmark: Track thread's CPU utilisation time

SELFOUR-446 Benchmark: Track syscall feature

Benchmark feature that currently:
- Keeps track of system calls info
- Start time
- Duration
- Capability type
- Invocation tag
- Log the number of invocations of each system call*
- Log the number of invocations for each capability type per syscall.
- Has 3 new syscalls (dump, reset, get size).
- This new feature uses the existing log buffer (which is 1MiB for x86
and ARM). Since the number of syscall invocations is not
deterministic, the logged number of invocations is limited by the size
of the buffer. I suggested to enable the users to pass their own
user-level buffer, to enable more flexibility, later.
- ENABLE_BENCHMARKS is now a parent config option of trace points and
system call track features, they can't be used at the same time.

Removed CONFIG_BENCHMARK config option. All checks for '#ifdef CONFIG_BENCHMARK' replaced with '#if CONFIG_MAX_NUM_TRACE_POINTS > 0'.

Release snapshot