eventdev: bump library version

eventdev: bump library version

Bumping the library version to reflect the ABI change, where
rte_event_pmd_pci_probe(), rte_event_pmd_pci_remove(),
rte_event_pmd_vdev_init(), rte_event_pmd_vdev_uninit()
functions removed from the library.

Fixes: b1b3d9f90502 ("eventdev: make vdev init and uninit functions optional")
Fixes: 9a8269d56942 ("eventdev: make PCI probe and remove functions optional")

Reported-by: Thomas Monjalon <thomas@monjalon.net>
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>