Fixed incorrect divisor procurve current sensor divisor (#8836)

This is a fix for #8746, which added support of SFP module discovery on Procurve devices. I noticed a lot of false positive alerts for current bias when we launched this in production, so looked once more through MIB/code. 

MIB data: 
hpicfXcvrBias - Tx bias current in microamps
hpicfXcvrBiasHiAlarm - Transceiver bias high alarm threshold limit in microamps
hpicfXcvrBiasLoAlarm - Transceiver bias low alarm threshold limit in microamps

Sensor discovery sample: 
hpicfXcvrBias.49 = 23254
hpicfXcvrBiasHiAlarm.49 = 100000
hpicfXcvrBiasLoAlarm.49 = 0
hpicfXcvrBiasHiWarn.49 = 90000
hpicfXcvrBiasLoWarn.49 = 100

So yes, my mistake was to use 10^-7 instead of 10^-6 divisor for these fields. Fix is in this pull request. Sorry for the inconveniences caused. 

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includes/discovery/sensors/current/procurve.inc.php

@@ -1,7 +1,7 @@
 <?php
 $multiplier    = 1;
 $divisor       = 1000000;
-$divisor_alarm = 10000000;
+$divisor_alarm = 1000000;
 foreach ($pre_cache['procurve_hpicfXcvrInfoTable'] as $index => $entry) {
     if (is_numeric($entry['hpicfXcvrBias']) && $entry['hpicfXcvrBias'] != 0) {
         $oid                       = '.1.3.6.1.4.1.11.2.14.11.5.1.82.1.1.1.1.13.' . $index;