event/cnxk: fix symbol map

Caught while rebasing a series that check map files.

Remove superfluous whitespace.
Current ABI number is 24.
Sort experimental symbols and annotate them with the version they are
introduced in.

Fixes: 03714a4 ("event/cnxk: add event port flow context API")

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>

drivers/event/cnxk/version.map

@@ -1,9 +1,11 @@
- DPDK_23 {
+DPDK_24 {
 	local: *;
- };
+};
 
- EXPERIMENTAL {
+EXPERIMENTAL {
 	global:
-	rte_pmd_cnxk_eventdev_wait_head;
+
+	# added in 23.11
 	rte_pmd_cnxk_eventdev_is_head;
- };
+	rte_pmd_cnxk_eventdev_wait_head;
+};