ARM: tegra: increase console buffer size and sys args num

The Linux-for-Tegra kernel uses a very long command line.

The default value of CONFIG_SYS_CBSIZE is too small to printf out the
long command line and causes a message like:
  bootarg overflow 602+0+0+1 > 512
on the console, and the board refuses to boot.

The default value of CONFIG_SYS_MAXARGS is too small to add a long
long command line, and the kernel won't boot without the complete
bootargs.

Increasing these two config options solves this problem.

Signed-off-by: Bryan Wu <pengw@nvidia.com>
Signed-off-by: Peter Chubb <Peter.Chubb@data61.csiro.au>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>