libmemhack: add growing config transfer and parsing

We have growing config parsing and output in ugtrain. Now transfer
this config via the input FIFO to libmemhack. Parse it there and
return the read config output. FIFO data looks like this:

1;0;0x0;0x0;grow;16;40;0x754;0x8

The key word "grow" followed by a ';' marks that there is a growing
configured for this object.

The debug output looks like this:

[memhack] config[0]: mem_size: 0; code_addr: 0x0; stack_offs: 0x0
[memhack] config[0] growing: size_min: 16; size_max: 40; \
code_addr: 0x754; stack_offs: 0x8