KVM: x86: optimize more exit handlers in vmx.c

[ Upstream commit f399e60c ]

Eliminate wasteful call/ret non RETPOLINE case and unnecessary fentry
dynamic tracing hooking points.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stable-dep-of: 31de69f4 ("KVM: nVMX: Properly expose ENABLE_USR_WAIT_PAUSE control to L1")
Signed-off-by: Sasha Levin <sashal@kernel.org>