staging: pi433: fix wrong debug message on rf69_write_fifo()

The debug message should describe error when user calls rf69_write_fifo()
not rf69_write_fifo().

Signed-off-by: Sidong Yang <realwakka@gmail.com>
Link: https://lore.kernel.org/r/20220730012724.1138-1-realwakka@gmail.com


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