patch 8.2.4989: cannot specify a function name for :defcompile

Problem:    Cannot specify a function name for :defcompile.
Solution:   Implement a function name argument for :defcompile.
diff --git a/src/ex_cmds.h b/src/ex_cmds.h
index e4f9bb0..b8cf41d 100644
--- a/src/ex_cmds.h
+++ b/src/ex_cmds.h
@@ -465,7 +465,7 @@
 	EX_EXTRA|EX_BANG|EX_SBOXOK|EX_CMDWIN|EX_LOCK_OK,
 	ADDR_NONE),
 EXCMD(CMD_defcompile,	"defcompile",	ex_defcompile,
-	EX_SBOXOK|EX_CMDWIN|EX_LOCK_OK|EX_TRLBAR,
+	EX_SBOXOK|EX_CMDWIN|EX_LOCK_OK|EX_TRLBAR|EX_EXTRA,
 	ADDR_NONE),
 EXCMD(CMD_delcommand,	"delcommand",	ex_delcommand,
 	EX_NEEDARG|EX_WORD1|EX_TRLBAR|EX_CMDWIN|EX_LOCK_OK,