Staging: btmtk_usb: Fix Sparse Warning of incorrect type in assignment

This patch fixes the following Sparse Warnings in btmtk_usb.c:

drivers/staging/btmtk_usb/btmtk_usb.c:676:39: warning: incorrect type in assignment (different base types)
drivers/staging/btmtk_usb/btmtk_usb.c:676:39:    expected unsigned int [unsigned] [usertype] packet_header
drivers/staging/btmtk_usb/btmtk_usb.c:676:39:    got restricted __le32 [usertype] <noident>

drivers/staging/btmtk_usb/btmtk_usb.c:736:31: warning: incorrect type in assignment (different base types)
drivers/staging/btmtk_usb/btmtk_usb.c:736:31:    expected unsigned int [unsigned] [addressable] [usertype] packet_header
drivers/staging/btmtk_usb/btmtk_usb.c:736:31:    got restricted __le32 [usertype] <noident>

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>