[][kernel][common][eth][Update firmware download feature for Aquantia PHY driver]

[Description]
Refactor firmware download feature for Aquantia PHY driver.
    - Add a spinlock to protect firmware download function.
    - Change single download mode to wait method.
    - Change re-configure PHY method to avoid Flow Control setting loss.

If without this patch, PHY might lose Flow Control setting when
disabling CONFIG_AQUANTIA_PHY_MDI_SWAP.

[Release-log]
N/A


Change-Id: I0f8a559bc7a25338b1eba07c08ceaad0f6cd5bf2
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/6916308
1 file changed