selftests/bpf: verifier/value_ptr_arith converted to inline assembly

Test verifier/value_ptr_arith automatically converted to use inline assembly.

Test cases "sanitation: alu with different scalars 2" and
"sanitation: alu with different scalars 3" are updated to
avoid -ENOENT as return value, as __retval() annotation
only supports numeric literals.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230421174234.2391278-25-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>