libiproute: handle table ids larger than 255

libiproute: handle table ids larger than 255

Linux kernel, starting from 2.6.19 allows ip table ids to have 32-bit values.
In order to preserve compatibility, the old 8-bit field: rtm_table is still
in use when table id is lower than 256.

Add support for the 32-bit table id (RTA_TABLE attribute) in:
- ip route print
- ip route modify
- ip rule print
- ip rule modify

Add printing of table ids to ip route.

Changes are compatible with the mainline iproute2 utilities.

These changes are required for compatibility with ConnMan, which by default
uses table ids greater than 255.

function                                             old     new   delta
print_route                                         1588    1637     +49
do_iproute                                          2187    2222     +35
do_iprule                                            955     987     +32
print_rule                                           617     630     +13
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/0 up/down: 129/0)             Total: 129 bytes

Signed-off-by: Lukasz Nowak <lnowak@tycoint.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>