arch/x86/kvm/ioapic: Remove license boilerplate with bad FSF address

arch/x86/kvm/ioapic: Remove license boilerplate with bad FSF address

The Free Software Foundation does not reside in "59 Temple Place"
anymore, so we should not mention that address in the source code here.
But instead of updating the address to their current location, let's
rather drop the license boilerplate text here and use a proper SPDX
license identifier instead. The text talks about the "GNU *Lesser*
General Public License" and "any later version", so LGPL-2.1+ is the
right choice here.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20250728152843.310260-1-thuth@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>