support global scalar constants
support global scalar constants

support kind of "constant int n = 1;"

collect scalar value in constant collector
also do virtual register translation for scalar constants

Signed-off-by: Homer Hsing <f17cb7083eb6a94c3fb9d8f09ceefa518f721ab2@intel.com>
Reviewed-by: Zhigang Gong <e04a7b9b70b1e4c6318cf117dcd1a9056e14b97a@linux.intel.com>

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