mt76: mt7915: fix some sparse warnings

This fixes the following sparse warning:

drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:253:16: sparse: sparse: mixing different enum types:
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:253:16: sparse:    unsigned int enum mt7915_txq_id
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:253:16: sparse:    unsigned int enum mt76_txq_id
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:758:63: sparse: sparse: incorrect type in argument 2 (different address spaces)
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:758:63: sparse:    expected unsigned char const [usertype] *ies
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:758:63: sparse:    got unsigned char const [noderef] <asn:4> *
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1390:23: sparse: sparse: incorrect type in argument 1 (different base types)
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1390:23: sparse:    expected unsigned int w
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1390:23: sparse:    got restricted __le32 [usertype] supp_ht_mcs
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1390:23: sparse: sparse: restricted __le32 degrades to integer
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1429:60: sparse: sparse: bad assignment (>>=) to restricted __le16
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:1773:16: sparse: sparse: restricted __le32 degrades to integer

Fixes: 6094f86f ("mt76: mt7915: add HE bss_conf support for interfaces")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>