scsi: core: Fix -Wformat for scsi_host

Clang is more aggressive about -Wformat warnings when the format flag
specifies a type smaller than the parameter. Turns out, struct Scsi_Host's
member can_queue is actually an int. Fixes:

[-Wformat]
shost_rd_attr(can_queue, "%hd\n");
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                          %d

Link: https://github.com/ClangBuiltLinux/linux/issues/378
Link: https://lore.kernel.org/r/20201107081132.2629071-1-ndesaulniers@google.com


Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
warning: format specifies type 'short' but the argument has type 'int'