spi: spi-rspi: Drop redeclaring ret variable in qspi_transfer_in()

spi: spi-rspi: Drop redeclaring ret variable in qspi_transfer_in()

"ret" variable is already declared in qspi_transfer_in() at the
beginning of function, drop redeclaring ret in the if block, fixing
below:

spi-rspi.c: In function ‘qspi_transfer_in’:
spi-rspi.c:838:7: warning: declaration of ‘ret’ shadows a previous local
  838 |   int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
      |       ^~~
spi-rspi.c:835:6: note: shadowed declaration is here
  835 |  int ret;

Fixes: db30083813b55 ("spi: rspi: avoid uninitialized variable access")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211118031041.2312-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>