Description:
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When using rrd_lastupdate on a rrd file with multiples values, the data array only contain one value, but the ds_navm array contain multiples values.

The data array shouldn't use timestamp as key in rrd_lastupdate, but the ds_name (or ds_index), to support multiple values.



Test script:
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$values = rrd_lastupdate("my_multiples_values_rrd_file");;
print_r($values);

Expected result:
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The data array should contain values for each ds.

Actual result:
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The data array contain only one value and the index is the timestamp.