can: softing: Remove redundant variable ptr

The value stored to ptr in the calculations this patch removes is not
used, so the calculation and the assignment can be removed.

Cleans up the following clang-analyzer warning:

drivers/net/can/softing/softing_main.c:279:3: warning: Value stored to
'ptr' is never read [clang-analyzer-deadcode.DeadStores].

drivers/net/can/softing/softing_main.c:242:3: warning: Value stored to
'ptr' is never read [clang-analyzer-deadcode.DeadStores].

Link: https://lore.kernel.org/r/1619520767-80948-1-git-send-email-jiapeng.chong@linux.alibaba.com


Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>