scsi: aacraid: mark aac_src_select_comm() static

scsi: aacraid: mark aac_src_select_comm() static

We get 1 warning when building kernel with W=1:
drivers/scsi/aacraid/src.c:616:5: warning: no previous prototype for 'aac_src_select_comm' [-Wmissing-prototypes]

In fact, this function is only used in the file in which it is declared
and don't need a declaration, but can be made static.  so this patch
marks this function with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dave Carroll <david.carroll@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>