spi-topcliff-pch: fix -Wuninitialized warning

spi-topcliff-pch: fix -Wuninitialized warning

commit de3bd7e6de25141c466773c2e0fa319b2fa93655 upstream.

Fix for:
drivers/spi/spi-topcliff-pch.c: In function ‘pch_spi_handler_sub’:
drivers/spi/spi-topcliff-pch.c:325:17: warning: ‘bpw_len’ may be
  used uninitialized in this function [-Wuninitialized]
drivers/spi/spi-topcliff-pch.c:325:42: warning: ‘rx_index’ may be
  used uninitialized in this function [-Wuninitialized]
drivers/spi/spi-topcliff-pch.c:325:42: warning: ‘tx_index’ may be
  used uninitialized in this function [-Wuninitialized]

Move usage of tx_index, rx_index and bpw_len into the same
block as where they are set to prevent uninitialized usage.

v2: instead of init variables with 0 move the whole block

[This patch title "warnings" makes you think "This patch is not
for bug fix".  However, this patch surely patch for bug fix.]

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>