usb: gadget: udc: Remove useless variable assignment in xudc_read_fifo()

This patch removes the unused variables assignment warning.
Value assigned to variable bufferspace is overwritten, before
it can be used. This makes such variable assignment useless.

Reported Coverity warning: UNUSED_VALUE

Signed-off-by: Piyush Mehta <piyush.mehta@xilinx.com>
Link: https://lore.kernel.org/r/20220506175349.10102-1-piyush.mehta@xilinx.com


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