tools/mesh-cfgclient: Add address checks for pub/sub commands

tools/mesh-cfgclient: Add address checks for pub/sub commands

This addrs verification of subscriptpion address value entered on
the command line: unassigned address, unicast address, and
all-nodes address are not allowed. Publication address check verifies
that the entered value falls into mesh address space.

Also, change the type of parameter count in comaand processing routines
from int to uint32_t to match the retrun type of the parameter parsing
routine.

Change-Id: Ib5747a132e59e4af5f21dbad5319167234230548
Signed-off-by: Anupam Roy <anupam.r@samsung.com>