ANDROID: KVM: arm64: Add func/func_ret pKVM hyp events

Those events are raised for whenever a function is entered and exit at
EL2. They rely on Ftrace in the pKVM hypervisor and the later must be
enabled with CONFIG_PROTECTED_NVHE_FTRACE.

Bug: 357781595
Change-Id: Ife7649fba88779ba3bb8bb7f11bbab244141200b
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>