mt76: mt7915: rename mt7915_mcu_get_rate_info to mt7915_mcu_get_tx_rate

mainline inclusion
from mainline-v5.11-rc1
commit e4c5ead6
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I94J23
CVE: CVE-2021-47028

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e4c5ead632ffd87fc387f306b9e622fe52e97e5a



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Avoid confusion with rx rate query function.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Conflicts:
	drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>