vm/jar: Clean up code

Reading vm/jar.c can feel like pulling teeth at times...

Signed-off-by: Pekka Enberg <penberg@kernel.org>
vm: include native trampolines in stack traces

Signed-off-by: Tomasz Grabiec <tgrabiec@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
vm: fix missing new line after vm native trace element

Signed-off-by: Tomasz Grabiec <tgrabiec@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
x86-64: Enable StackTraceTest

Signed-off-by: Pekka Enberg <penberg@kernel.org>