make hpet_find inline so we don't need
to build hpet.c to check if hpet is enabled.
Fixes link error with CONFIG_HPET off.
Cc: qemu-stable@nongnu.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 142e0950cf)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>