meter: unify packet color definition

meter: unify packet color definition

Added new rte_color definition in librte_meter to
consolidate color definition which is currently replicated
in various places such as rte_meter.h, rte_tm.h and rte_mtr.h

Created aliases for rte_tm_color, rte_mtr_color and rte_meter_color
to use new rte_color values.

The definitions of rte_tm_color, rte_mtr_color and rte_meter_color
will be deprecated in future.

Signed-off-by: Jasvinder Singh <jasvinder.singh@intel.com>
Signed-off-by: Reshma Pattan <reshma.pattan@intel.com>
Acked-by: Cristian Dumitrescu <cristian.dumitrescu@intel.com>