ARM: bootscript: Fix the nfsargs and addip in K+P's tpcboot.cmd

The quotes around ${bootargs} were missing as we elaborate those variables
twice - once when we "setenv" the command and secondly when we "run" it.
Without quotes we have just empty string in the second call.

Moreover there is an issue with line breaks - as the original commands
got truncated.

Signed-off-by: Lukasz Majewski <lukma@denx.de>