[][MAC80211][app][Add MT7988 case in smp-mt76.sh]

[Description]
Add MT7988 case in smp-mt76.sh
With this patch, it would use the following setting
- wireless interface (wlan* and phy*)
  - rps = 0x7
  - smp_affinity = 0
- ethernet interface
  - rps = 0
  - smp_affinity = 4 and 8

[Release-log]
N/A

Change-Id: I2dbccbd883f90c9d13a8c6537868951fe03bb463
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7015710
1 file changed