Bluetooth: btmtk: Remove the resetting step before downloading the fw

Remove the resetting step before downloading the fw, as it may cause
other usb devices to fail to initialise when connected during boot
on kernels 6.11 and newer.

Signed-off-by: Hao Qin <hao.qin@mediatek.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>