fpga: dfl: afu: Corrected error handling levels

Corrected error handling goto sequnece. Level put_pages should
be called when pinned pages >= 0 && pinned != npages. Level
free_pages should be called when pinned pages < 0.

Fixes: fa8dda1e ("fpga: dfl: afu: add DFL_FPGA_PORT_DMA_MAP/UNMAP ioctls support")
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/1589825991-3545-1-git-send-email-jrdr.linux@gmail.com


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