apalis/colibri_t30: add misc cmds increase buf sizes and max args

In order to work with our downstream U-Boot environment and update
scripts add support for the following miscellaneous commands:

CONFIG_CMD_SETEXPR
CONFIG_FAT_WRITE

Increase the console I/O and print as well as argument buffer sizes:

CONFIG_SYS_CBSIZE
CONFIG_SYS_PBSIZE
CONFIG_SYS_BARGSIZE

Increase the maximum number of arguments allowed:

CONFIG_SYS_MAXARGS

Signed-off-by: Marcel Ziswiler <marcel@ziswiler.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>