usb: host: fotg210: Fix a function name in comments

Use dma_map_single() instead of pci_map_single(),
because only dma_map_single() is called here.

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210925124920.1564-2-caihuoqing@baidu.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>