scsi: mptfusion: Remove unnecessary parentheses

Clang warns when multiple pairs of parentheses are used for a single
conditional statement.

drivers/message/fusion/mptbase.c:338:11: warning: equality comparison
with extraneous parentheses [-Wparentheses-equality]
if ((ioc == NULL))
~~~~^~~~~~~
drivers/message/fusion/mptbase.c:338:11: note: remove extraneous
parentheses around the comparison to silence this warning
if ((ioc == NULL))
~ ^ ~
drivers/message/fusion/mptbase.c:338:11: note: use '=' to turn this
equality comparison into an assignment
if ((ioc == NULL))
^~
=
drivers/message/fusion/mptbase.c:342:12: warning: equality comparison
with extraneous parentheses [-Wparentheses-equality]
if ((pdev == NULL))
~~~~~^~~~~~~
drivers/message/fusion/mptbase.c:342:12: note: remove extraneous
parentheses around the comparison to silence this warning
if ((pdev == NULL))
~ ^ ~
drivers/message/fusion/mptbase.c:342:12: note: use '=' to turn this
equality comparison into an assignment
if ((pdev == NULL))
^~
=
2 warnings generated.

Remove them and while we're at it, simplify the NULL checks as '!var' is
used more than 'var == NULL'.

Reported-by: Nick Desaulniers <[e-mail]>
Signed-off-by: Nathan Chancellor <[e-mail]>
Reviewed-by: Nick Desaulniers <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/message/fusion/mptbase.c

···
 	MPT_ADAPTER *ioc = (MPT_ADAPTER *)arg;
 	struct pci_dev *pdev;
 
-	if ((ioc == NULL))
+	if (!ioc)
 		return -1;
 
 	pdev = ioc->pcidev;
-	if ((pdev == NULL))
+	if (!pdev)
 		return -1;
 
 	pci_stop_and_remove_bus_device_locked(pdev);