net/ena: remove useless address check

net/ena: remove useless address check

Reported by "gcc (GCC) 12.0.0 20211003 (experimental)":

./drivers/net/ena/ena_rss.c: In function ‘ena_rss_reta_query’:
./drivers/net/ena/ena_rss.c:140:66:
	error: the comparison will always evaluate as ‘false’ for the
	pointer operand in ‘reta_conf + 136’ must not be NULL
	[-Werror=address]
  140 |  (reta_size > RTE_RETA_GROUP_SIZE && ((reta_conf + 1) == NULL)))
      |                                                       ^~

Fixing it by removing useless check.

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Michal Krawczyk <mk@semihalf.com>